Interviews - L. Mario Amzel 

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An Interview with Mario Amzel

By David Zierler 

March 20, 2020 

Location: Essex, Maryland


ZIERLER: This is David Zierler, oral historian for the American Institute of Physics. It is March 20th, 2020. It is my great pleasure to be here in Essex, Maryland at the home of Dr. Mario Amzel. Dr. Amzel, thank you so much for being with me today.


AMZEL: Thank you for doing this, yes.


ZIERLER: Okay, okay, so. We are going to start right at the beginning of your long and illustrious life. Please tell me a little bit about your childhood, your family, your birthplace.


AMZEL: Okay. Okay. Family, I grew up in a working class neighborhood. No, the family could move you know, like middle class, as my father had a shoe store in a working class neighborhood, so in reality, that doesn't put you above working class as a, as a social environment. Went to public schools for grammar school. Went to what in Argentina still is called "normal school," and that is after five years of high school, you come out a teacher. High school teacher. So that was my degree, but at that moment, I could go to the university anywhere. I wanted to go into math, but if it didn't kill my father, it was close. (laughs)


ZIERLER: Where were your father and mother born?


AMZEL: Born, they were born in Europe. They were essentially from the Austrian-Hungarian Empire, Because the, geography changed at the beginning of the century.




AMZEL: But essentially in Austria.


ZIERLER: Now, "Mario" would suggest at some point there's Italian heritage?


AMZEL: No, it was a very popular name. At this moment, there are two Marios in the lab. There was a third Mario, which is Mario Bornia, who is in the research triangle, and it was a very popular name for many years, and so they liked it and...


ZIERLER: So your parents were essentially from Austria, both of them?


AMZEL: Yes, yes.


ZIERLER: And when did they come to Buenos Aires?


AMZEL: I would say in the 20s, but they were not married. They met in Buenos Aires.


ZIERLER: They met in Buenos Aires?


AMZEL: Yes. Yes.


ZIERLER: And what was their language? What did they speak to each other in?


AMZEL: Well, they speak-- well, that's why they think the geography was changing, because where my father was, it remained Poland. Where my mother was, it did not remain Poland, but they both knew Polish. So that was their language.


ZIERLER: That they spoke to each other?




ZIERLER: Uh-huh. And why did each of them separately come to Argentina?


AMZEL: They both have brothers or sisters.




AMZEL: And my father had a brother that he joined, and my sister had a brother-- two brothers, that she joined.


ZIERLER: Now, your father was a, was he a cobbler? A shoe cobbler?


AMZEL: Then, I, I think originally that's what he was, yes, yes. But well he, when I was I child, that's what he was, yes.


ZIERLER: Yeah. So he made shoes, he didn't just sell them?


AMZEL: No made. Fixed them.


ZIERLER: He fixed them?




ZIERLER: And your mother, she worked in the house? Or she worked outside--?


AMZEL: The house, she also take care of the store because my father also did some wholesale selling. So he was outside the store for some time and she would take care of the store.


ZIERLER: You had brothers and sisters?


AMZEL: I have one sister.


ZIERLER: Uh-huh. Older or younger?


AMZEL: Is five years older.


ZIERLER: Uh-huh. Uh-huh. And your school, you went to public school or private school?


AMZEL: All public schools.


ZIERLER: And what did you speak growing up? Spanish was your first language?


AMZEL: Yes, yes. The only language. Yes.


ZIERLER: The only language. So you spoke to your parents in Spanish?


AMZEL: Oh yes.


ZIERLER: Uh-huh. Okay, and when did you start to develop your interest in science?


AMZEL: Well, mostly at the university. Science in high school is not very tempting, so you know, it is in Argentina, college is free.




AMZEL: But you still have to live somewhere. So you need an income if you're going to be outside your parents' house. That was not my choice at the time. Eventually, very, very soon, I got a scholarship, and I could move, but at that time I had to compromise and live with my parents. So my father was of the idea-- my mother, whatever I did was right and it was no issue­–my father always thought that one goes to the university to get a degree of a profession. Accountant, lawyer, physician. So "chemist" sounded like a liberal profession. So I registered in chemistry in the university. You know, from the first few months, I realized that one could do something which was different than remembering the, the periodic table. (laughs) And I started to work in the lab there as a sophomore, yes.


ZIERLER: At what point did you--


AMZEL: As a freshman, sorry.


ZIERLER: Yeah. At, at what point did you convince your father that this was a viable career option for you?


AMZEL: Never.




AMZEL: Never, no, no. No, no. No, no. No.


ZIERLER: What did he want you to do?


AMZEL: No. the idea was that you know, for a long time before he came here, and for some time that he was here before I was born, he was an employee, he was working for somebody. He always wanted to study, but he didn't have the opportunity, so he didn't understand why anybody will study and still working for somebody, even if it is the government. That was never clear to him.




AMZEL: That with your studies has to become your own person.




AMZEL: The fact that you know, if you're a scientist, you are your own person, it wasn't true because you depended on a salary and on things like that.




AMZEL: So that never happened.


ZIERLER: But your mom, she was supportive?


AMZEL: Oh, she, oh yes. Whatever I did was perfect, yes.


ZIERLER: Really?


AMZEL: Yes, yes.


ZIERLER: Did your sister follow a scientific path as well?


AMZEL: No. No, she, she eventually... She was the editor of the magazine of the interdeveloping bank, until they closed the magazine. That was probably 20 years ago, and then at that moment, she retired. She lived in Argentina and now actually since August, she's living here with me.


ZIERLER: So your undergraduate education, did you take all science classes, or you also took literature and things like that?


AMZEL: No, the university doesn't work that way. You could take them, but they are not required, they are not consider good credits, either. So--


ZIERLER: So you focused exclusively on science classes?


AMZEL: On Science, so I took math, physics, and chemistry. And then as a pre-freshman classes I took geology and biology. But those were just, I would say, high school level.


ZIERLER: Were there professors that you became close with as an undergraduate?


AMZEL: Yes, oh yes. Yes, because I did work in research the whole time.


ZIERLER: You did?




ZIERLER: What kind of projects were you working on?


AMZEL: The ones that I spent more time on I understood the best were electrochemistry. And electrochemistry in two things: mechanistically and analytically.


ZIERLER: And what did you like about that?


AMZEL: Well, I liked the physics and thermodynamics of that, and you know, any of these projects brings first principle physics and, you know, as secondary physics, like diffusion, and things related to flows and things like that. So those are not, they are physics but not first principle physics, they are just... You know, made up equations, but also bring up thermodynamics, electrochemical potentials, and relation to concentrations, activities, all the...


ZIERLER: Now, were the projects you were working on directed by professors, or these were your own projects that you had developed?


AMZEL: No, they were directed by professors, but they were just, you know, in general, they were, they would take-- I did not invent them, but I did cover them up.


ZIERLER: Uh-huh. Did you engage in discussions with your professors about what your next move would be, after your undergraduate studies?


AMZEL: That's a good question.


ZIERLER: Like who gave you-- certainly it wouldn't have been your father, right?




ZIERLER: Who would have given you advice about what to do after your undergraduate degree? Or what did you think that you wanted to do?


AMZEL: Yes, it, it is-- it was, even though it is the largest university in the country, the number of people that I interacted with in things that I was interested in was very small. So I would say at the end, everything was down to, well, only four or five people. I did not--


ZIERLER: Why did it become so small? People left the program?


AMZEL: Well, I, I can tell you. For example, I was in chemistry. I wasn't going to do synthetic organic chemistry.


ZIERLER: Why not?


AMZEL: Because this is not first principle enough.


ZIERLER: Ah-hah. So you were determined to do purely first principle physics?


AMZEL: If possible, yes.


ZIERLER: Why? What was so exciting about that to you?


AMZEL: Well, because each time I understood something of the level of the basic physics, I thought that I understood it. Nothing else I thought I understood.


ZIERLER: Uh-huh.


AMZEL: So for example, one thing that was very strong in the department I did my undergrad with, no the emphasis, the mas-- major, was extraordinary very good kinetics. Was the time of the boron compounds, and--




AMZEL: And it really was uninteresting to me. Kinetics was an empirical science.




AMZEL: It doesn't relate to first principles. Nobody tells why the reaction goes "this" fast based on first principles, it tells only because it's full of some equations that we know will make it go fast. That did not appeal to me. So I didn't do kinetics.




AMZEL: Because I could have done quantum mechanics, but since childhood I liked to find out how all kind of objects work, so not doing experiment was maybe a deterrent. So then I could do pure thermodynamic measurements, or I can try to do system-based things, which is to choose a problem for which I try know how a given system works. And that appealed the most, and one of the faculty was working on structural thermodynamics, and that's what appealed to me, which is relating thermodynamics to structure, which is thermodynamics in which you will identify the species which are thermodynamically competent. What are the structural equivalents? What are, where are the atoms in those structures?




AMZEL: So he was working on plastic crystals and liquid crystals. Crystals that has phase-to-phase transitions that were not to a liquid, not a direct formal liquid. And so I went for plastic crystals and that's my doctoral thesis. So it's structural thermodynamics of plastic crystals. I still used structural thermodynamics to define my lab, yes, so nothing much changed.


ZIERLER: Was it unusual to write an undergraduate thesis, or most students did?


AMZEL: No, sorry, that was not the undergraduate thesis, that was the graduate thesis.


ZIERLER: Oh, okay.




ZIERLER: All right, so--


AMZEL: Undergraduate thesis, no. I, I worked on several things and I did work on other things, for example, in one of our laboratories for physical chemistry, we did measure activities by measuring vapor pressures. And it is a classical experiment.  Well, sort of. And every student group made one point. It was the alcohol-water system. And then we traced the lines and we calculated the free-energies. At that moment, as I told you, I was interested in math, and I said, "Oh, come on. Why are we going to draw a line? I could try to find the best parameters as a minimum with a least-squares algorithm. Problem is the computer has just arrived to the university. I have an article here that says that it arrived in 1961; I took the first course they offer in programming, was in language call Autodoc, with which, instead of having to write 100100, you could write an instruction. (both laugh) I did not use the computer for the lab experiment (I used it heavily later), I wrote an algorithm that, you know, I can go through it and adjust those data points to a curve and get statistics, for example. So those are the kind of things I did as an undergrad. Those are not a thesis.


ZIERLER: Right, right. Now, so what year did you graduate undergraduate?


AMZEL: It's a complicated story. Oh, undergraduate is not a complicated story. This is, I finish in 1964, under-graduation was 1969-- '64, '65.


ZIERLER: Okay. And what was your degree in when you graduated?


AMZEL: Licenciado with a qualification is in chemistry. Is not a general title, is a, is a title with a major.




AMZEL: So licenciado en química. And, and by then, I said 1965, and the end of 1964, because I already started working in the thesis in 1964.


ZIERLER: On your graduate thesis?


AMZEL: The graduate thesis, yes.


ZIERLER: So you were already talking with your professors about staying on as a graduate student?


AMZEL: Yes, yes. And I already had a fellowship at that time. I was-- It's not called a fellowship, it's a TA but is a, (ZIERLER: Teaching Assistantship?) they knew I would TA-- yes. Teaching Assistantship, but is renewable so it's not that you have to go in-- if, if they want.


ZIERLER: Right. Did you consider going elsewhere for your graduate work, or you just felt you were there, keep--




ZIERLER: Continue on?


AMZEL: I, I did not consider go anywhere else, no.


ZIERLER: Were you living at home at this time, also?


AMZEL: Let me see... It's '64... 22, I got married around '64, so depends on the time I was not living at home already, yes.


ZIERLER: Okay. So you were living at home for most of your undergraduate.


AMZEL: All of the undergraduate, yes.


ZIERLER: Where did you meet your wife?


AMZEL: At the university.


ZIERLER: Oh, she was a fellow student?


AMZEL: Yes, yes.


ZIERLER: In science?


AMZEL: In science, yes. The story is very complicated, but I'm divorced like 25 years now, yes.


ZIERLER: Okay. So you graduated and then you decided to stay on...


AMZEL: Correct.


ZIERLER: For your graduate degree.


AMZEL: Well, one thing that, maybe it would become clear, maybe not, I mean I don't know if you want to write it, is too complicated, is that at that time, or maybe other time before '66, I never consider about leaving Argentina in any way.


ZIERLER: You were?


AMZEL: I was not.


ZIERLER: You were not.


AMZEL: Correct. I just wanted to finish my PhD and go into a faculty position there, and that will be my life. No--


ZIERLER: Yeah, yeah. When did you decide that you wanted to enter academia, to become a professor? As an undergraduate or later on?


AMZEL: You know, that it wasn't even a decision. (ZIERLER: Yeah.) It w-- it was just... That seems to be (ZIERLER: The natural flow.) the way it was going to go, yes.


ZIERLER: Right, right.




ZIERLER: Now the professors you're working with as an undergraduate, you continue to work with them as a graduate student?


AMZEL: Yes, they were very, yeah, I, you know, I interacted with them. I was their TAs in some courses. We were part of, you know, just university affairs. I was, I don't remember enough, but I was one of the students representative in one of the student’s groups-- The university is a very forward looking institution.  In 1918, became a very forward looking university, so the students are part of the government. So I was one of them at some moment. The faculty is also a part of them, so they are representatives, and I interacted with them, so I interacted with most of the people I had interacted before, yes.


ZIERLER: And you were still in the, in the chemistry department?


AMZEL: Yes. in reality, they were branches, and I was in the physical chemistry.


ZIERLER: Physical chemistry.


AMZEL: Yeah.


ZIERLER: Was there a master’s degree, or that was just something that you got on your way to the doctorate?


AMZEL: No, there was not an MA. No, there was licenciado, licenciado is much more than a batchelor; it takes five years and there are many more courses in the subject than there are for a person that does college and has a major in chemistry. People that have a licenciado know much more chemistry than the people that here graduate with a major in chemistry. But people that graduate here and they major in chemistry, they know a lot about some chemistry.




AMZEL: For example, they, if they do organic synthesis, they are really good. They are really good. But for example, biochemistry, they know nothing. I had one year of biochemistry.


ZIERLER: Yeah, yeah.


AMZEL: With laboratory.


ZIERLER: Right, right. Were you taking courses as a graduate student? Or it was strictly lab work?


AMZEL: Here-- I had to take a few courses, yes.


ZIERLER: Uh-huh. But you were saying that your thesis, you had already begun developing as an undergraduate?


AMZEL: Correct. Correct.


ZIERLER: Now the thesis, you had come up with this idea on your own? Or it was in consultations with professors?


AMZEL: No, it was in consultation with the professor, Leo Becka. The thing, there are historical things that happened and they, and they will creep up.




AMZEL: Argentina had government by the person that half of Argentina considered autocratic tyrant, and half of the Argentina considered the best leader in history, which was Perón.




AMZEL: He was overthrown in 1955. Before that, the university was under a regime that clearly qualifies very much as a autocratic, authorities being manipulated and things like that. When he was overthrown, new authorities came. There was a short time, although there was a military government, they just did not have enough manpower to deal with the university the way they wanted, probably, so the university became very autonomous. And there were very good people that took over, and they sent their best undergraduates finishing to do a PhD abroad.




AMZEL: So all of the professors I'm mentioning in the group of professors I interacted with, had come back around the late 1950s with a PhD from Oxford, Cambridge, NYU, Hopkins, Stanford. So they were people that were, you know, well-trained in the latest of science.


ZIERLER: And they came back home?


AMZEL: They came back home, they did. Yes. So the person I chose for my thesis with, Leo Becka, he came from Scotland, (Leeds) from working with Cruickshank. He, Cruikshank was a god mathematician crystallographer. Is the one that wrote Refinement for the Crystallographic Tables.




AMZEL: My advisor did his doctorate with Cruikshank. And he did it on anisotropic refinement. And it was clear at that moment that anisotropic refinement had information about molecular motions that have thermodynamic information. So that was the subject that my thesis advisor had worked on. And for me, was exactly what I wanted to do. So, at the end, I did not get the molecular motions from temperature factors, just because the data were not good enough, but the idea is still good.


ZIERLER: What did you see as your major contributions to the field with this thesis?


AMZEL: To that one?




AMZEL: The paper we wrote is a model, it's a model for the thermodynamic transition, and that is just a thermodynamic model. This is an abstract model in which, you know, when you get this kind of model, you get what contributes to the transition; all the things that you get from a model. And then we wrote another paper in which I calculated heat capacities using a crystallographic and spectroscopic data.


ZIERLER: Did you see your work as having more theoretical value or more applied value?


AMZEL: At the time, you realize, LCDs (liquid crystal displays) have not been completely described yet, so I chose plastic crystals and not liquid crystals because, you know, I'm a person with good three-dimensional intuition. Plastic crystals are symmetry-based. Is suited, is a, you know, an extraordinary utilization of symmetry. And liquid crystals, although one could see where they were going, were more boring––flat molecules moving in a layered environment,


ZIERLER: Why is that more boring?


AMZEL: No, just because I like symmetry a lot.


ZIERLER: (laughs)


AMZEL: So, so in plastic crystal, the idea is that the symmetry of the molecule is lower than the point symmetry of the place the molecules are in the crystal. So it's very small changes in the crystallographic cell, you get the molecules to occupy symmetrical positions. And that is okay, is not that interesting, but if the molecules have almost-symmetry, quasi-symmetry, then they are going to occupied highly symmetrical positions but with multiple occupancies. And that was fun. That's sound interesting. (laughs)


ZIERLER: Why was that fun for you?


AMZEL: Sorry?


ZIERLER: Why was that fun for you?


AMZEL: No, because you can count things, you can actually... Yeah, you can go from coordinates to thermodynamics. And that's what I did since then, okay?




AMZEL: Everything I did was with that in mind. can you go from coordinates to thermodynamics?


ZIERLER: Now, at this point, I mean, given where your career ultimately heads, are you thinking about the health sciences? Are you thinking about applying this research to improving human health outcomes?


AMZEL: Oh, I did it for a long time now, yes, which is as I said, to do the kind of things I'm interested in doing, I have to choose a system.




AMZEL: So, the systems that I chose in the last 15, 20 years are all from the health system. People are working in them with something in mind for health.


ZIERLER: Right, but as a graduate student, were you thinking along these lines already?


AMZEL: No, not at all.


ZIERLER: You were not?


AMZEL: Not at all. No, no.


ZIERLER: Okay. So you defend your dissertation in, is it 1968?






AMZEL: I have to qualify now many things.


ZIERLER: Please.


AMZEL: 1966, there was a military coup.




AMZEL: And they did not ignore the university. So--


ZIERLER: Right. Which means what? What does it mean that they don't (AMZEL: Well, well--) ignore?


AMZEL: Well, they did not ignore, is they... We had our authorities that we had chosen, voted for, and whatever. They chose another person, they gave the person a new position that didn't exist in the by laws of the university. And was the boss of the university. And told us what to do. And we did not agree. So one day, we call for a massive meeting, and they send the National Guard and they, you know, they hammer us with clubs and they put us in jail for a few days.


ZIERLER: Really, that happened to you?


AMZEL: Oh yes, oh yes.


ZIERLER: Because you would not comply with the orders?


AMZEL: Well, because we were there admitting to see not to comply with their orders, yes.


ZIERLER: Uh-huh. Uh-huh.


AMZEL: Yes, so I was in jail a few days. I have a scar to remember one of the clubs.


ZIERLER: Really?


AMZEL: Yes, in the head. And so then we started to meet in groups outside, and there was a lot of solidarity from universities in Latin America and the United States and the Ford Foundation.


ZIERLER: Now, did you have a developed political ideology before this, or were you thinking more in terms of academic freedom?


AMZEL: This group was about academic freedom. The university was politicized, but at this level, everybody got together.




AMZEL: So it was not--


ZIERLER: So you weren't particularly political.






AMZEL: Well, you know, when you are contradicting a military government, you are political, but--


ZIERLER: Of course, of course.


AMZEL: But in a different sense. It was not a party issue.




AMZEL: One thing I was going to say... Yes, I want to mention that many groups in the United States were, not only there's the American groups in the United States were very supportive, and the Ford Foundation actually did official things to accommodate the people. And there is a group now that is trying to rescue information about that.




AMZEL: So people started to go to different places. Chile was one place where many people went. Places in the United States; those schools those schools did not accept groups, but they accepted individuals. Uruguay was another place.. And then we required x-ray equipment at the time. And the only place that even had or bought one for us was Venezuela. So a group of four people, and then a few other people, went to Venezuela. And I went there.


ZIERLER: What was your plan? Just to get out for a little while (AMZEL: Well, I had to ge--) and then come back?


AMZEL: I had to get out, otherwise you know, the career would be ended, I would have to take a job and...


ZIERLER: Yeah. So this is 1966, you leave for Venezuela?


AMZEL: '66, but I'm leaving in 19... maybe beginning of '67.


ZIERLER: Yeah. Are you attempting to keep up with your graduate work, or it's on pause at this point?


AMZEL: No, that... No, attempting to get up, yes.


ZIERLER: Keep it up. Yeah.


AMZEL: So I kept it up with equipment we had in Venezuela. I wrote the thesis and submit it.


ZIERLER: Who, who was the home institution in Venezuela? Who hosted you?


AMZEL: Universidad Central de Venezuela.


ZIERLER: Uh-huh, uh-huh. Did professors go to Venezuela as well?


AMZEL: Sorry? (ZIERLER: Did your professors--) Yes, oh yeah, the professor went to Venezuela. We went with the professor.


ZIERLER: So you went as a group to Venezuela?


AMZEL: We went as a group, but they gave us... Because, well, there was one thing, which is in Venezuela, because they didn't have a doctorate, and they were trying establish it, a doctorate was not required to be a faculty. So the people that were doing the doctorate in Argentina, were given faculty positions, and that was a very strong attraction. We had to teach and we all liked to teach. And I could finish my thesis there, presented it, presented it to the committee, and it went through the administrative cracks, and the committee call me, I defended the thesis in 19... the end of 1968, and I got a paper from the university that said I had completed all the requirements for a thesis.


ZIERLER: So your degree is from Venezuela or it's from Buenos Aires?


AMZEL: No, no, no. In Argentina, Argentina, yes, yes.


ZIERLER: So it's basically, it's a department in exile in Venezuela? Essentially.


AMZEL: Correct, correct. But on the other hand, there was some faculty that kept in the university. I chose from those faculty to be the readers of the thesis, and they accepted and they accepted the thesis. They gave the document, they presented the document to the university. It went through the administrative cracks. But I had the paper that said that I completed all the requirements.


ZIERLER: And who was your dissertation director?


AMZEL: It was the person from the university of Venezuela. Oh no, sorry. Now I remember. There was in the group of people that stay in Argentina, one person that had been, you probably heard about him: Ernesto Galloni.




AMZEL: Ernesto Galloni. He probably is there in the annals of the ACA. And he accepted to become my director when my director left the university. So he was my director. But then there was no graduation ceremony...




AMZEL: for the people, in my group, until later on. And my father, that never thought that I did the right thing fought very hard to get the diploma in a graduation ceremony, which finally he did.




AMZEL: I never went to graduation, because it was very complicated.


ZIERLER: When you went to Venezuela, your parents must have been worried about you?


AMZEL: Oh yes, oh yes, oh yes. Yes, yes.


ZIERLER: Did they try to convince you, or at least your father? "See, I told you, get out of the university."? "Come back home."?


AMZEL: No, no, at that moment they were concerned enough, because I was in jail. That they agreed that I should go.


ZIERLER: Yeah, yeah. And what about your wife? Did she go with you to Venezuela?


AMZEL: She came to Venezuela with me and she had not finished her undergraduate, so she registered as an undergraduate in Venezuela. I'm not sure if she ever finished there, because eventually one year later... It was very clear to me that if I wanted to do science, a career in Venezuela will not be very high profile science. So that I had to go to a primary place. So I contacted a few places in the US. At Hopkins, there was a laboratory that was run by a person from Argentina. He had left many years before.


ZIERLER: And what was his name?


AMZEL: Roberto Poljak.


ZIERLER: Uh-huh. Did you know Roberto beforehand?


AMZEL: No, no.


ZIERLER: You just knew, you knew his reputation?


AMZEL: He had been, you know, in touch, I don't know at what level. I think at the level of undergraduate or maybe more, with Galloni. That's all what I knew. But then I knew that he was doing a very—important work on antibody structure. And then I liked very much the idea of getting a subject where you can do structural thermodynamics. It was the ideal place, because it was binding. So there was no kinetics involved (laughs): It was binding.


ZIERLER: What is it-- what do you mean "binding"? What does "binding" mean?


AMZEL: Because it was the structure of a fragment of an antibody. I stayed a few years  and we were able to determine the structure of the first antibody fragment (Fab fragment) with Roberto. So that was a big, big hit. But when I chose it, back then I didn't know it would be such a big hit. What I knew is that it was something that I would be interested in thinking about, no? Having coordinates for something that has specificity of binding, no? Was the relation between the thermodynamics and the structure.


ZIERLER: Yeah. Now, when you defend in 1968, is returning to Argentina, this is not an option for you? You don't even consider it?


AMZEL: When I left, I didn't consider staying outside Argentina.


ZIERLER: You didn't consider staying outside Argentina?


AMZEL: Correct. By the end of '68, yes, because there was no way of going back, and staying in Venezuela--


ZIERLER: Right. Because why? Because it was too dangerous to go back to Argentina?


AMZEL: No, they wouldn't give me a position, I'm sure.


ZIERLER: They wouldn't give you a position. Right, right. And what about staying in, in Venezuela?


AMZEL: Well, that's what I meant. It would not be a significant profile career. Just considering the science around and what I can do, and you know, what are the expectations and all those things, was not... I'm not criticizing the place, there were really outstanding to me, but in this particular area, the, you know, building that area in that place would have not been something that I could do by myself.  It is not the kind of things I am good at doing, yeah.


ZIERLER: So how exactly did you connect with Roberto? Did you write a letter to him?


AMZEL: Yes, yes.


ZIERLER: And who told you about him? Who, who made this suggestion?


AMZEL: That, I was trying to remember, no, I was looking for a different place. He was one of the major laboratories, so.


ZIERLER: Right, right.


AMZEL: So it was just by asking people, his name will come up. And considering that he was  from Argentina.


ZIERLER: So it's almost just a happy coincidence that he happened to be Argentinian?


AMZEL: Correct.


ZIERLER: You might have gone to work with him just because of his field.


AMZEL: Correct, correct.


ZIERLER: So for you, Hopkins was the place to be?




ZIERLER: You didn't really look at other programs?


AMZEL: That's a good point. No, again, this was it.


ZIERLER: This was it, this was the top place.


AMZEL: Because I contacted him, and he said, "Oh, great, come."


ZIERLER: "Come." Right.


AMZEL: Yeah.


ZIERLER: How was your English at this point?


AMZEL: Not very good. Yeah, not very good.


ZIERLER: But you figured with Roberto, at least you could communicate with him.


AMZEL: At least I could talk to somebody, yes. Yes.


ZIERLER: (laughs) Okay, so you get to Hopkins in '69?


AMZEL: February '69.


ZIERLER: February 1969, and what's your, your title there? It's a postdoc; you're a post doc?


AMZEL: Yeah, I'm a post doc, yes. And that require... I started talking to him at the end of '68.




AMZEL: Before the university granted me that, that certificate of completion of the PhD requirements.




AMZEL: So Roberto very, very kindly was prepared to take me as a technician first.




AMZEL: If I didn't get that certificate, he couldn't get me as a post doc. When the university reopened administratively and gave me the certificate, it went for legalization through the ministeries and embassy and everything, and Hopkins got that certificate, they took me as a post doc, and my position was post doc. I'm being very candid, don't, don't print anything but... That's, I said, it was a very complicated few years, yes.


ZIERLER: Yeah. So what projects were you working on when you first got to Hopkins?


AMZEL: Essentially, one immunoglobulin; it was in effect a fragment from an immunoglobulin that came from a patient.  In patients that developed multiple myeloma, the multiple myeloma cells, which are of a same clone, the blood is invaded by a single cell clone. And those cells produce the same antibody. So antibody counts in the serum are very high. 50 milligrams per mL. So one physician in University of Chicago sent us the protein from one patient, Newman, so the protein was called "New" and we produced F.A.B.s which is a fragment that includes the binding site.


ZIERLER: What does Fab stand for?


AMZEL: Fragment for Antigen Binding. Which is the antigen binding fragment of the antibody. We crystalized the fragment, and in a few years, we determined the structure. We also determined its structure with a small molecule bound...


ZIERLER: And determining the structure has ultimately clinical value?


AMZEL: Of course, yes. Yes.


ZIERLER: How so? Explain that.


AMZEL: Well, it is the antibody story; is very, very complicated clinically. It is very clear that if you look at the advertising on TV, and for many medications that they mention, if in the name in parentheses, you look for the three last letters, they are "mab.", that is a monoclonal antibody. So probably billions or trillions of dollars a year. A monoclonal antibody treatment probably is between 20 and up thousand dollars a year. So probably billions or trillions of dollars are spent on antibodies for clinical treatment. Reaching there took many years.




AMZEL: The first thing was that for many reasons, since César Milstein, who invented the monoclonal antibodies, (inventing means a method of immortalizing antibodies of a given specificity) he did not patent it. He thought they should be for th…for humanity. That's the way I understood it. Maybe it was a mistake that he made, or maybe this is the true story. So--


ZIERLER: Did he feel like that was not the scientific way? To profit from this discovery?


AMZEL: That's what I got from people that knew him (including myself). Some people said that he just blew it. (ZIERLER: (laughs)) So, so that was a deterrent. Then the monoclonal antibodies which are in multiple myeloma are mouse antibodies because you have to be able to grow them, and for that you combine them with a mouse tumor. Those antibodies, to be able to be injecting into humans without a gross antigenic response, they have to be humanized. We and other people indicated who to humanize them very early. But maybe the companies didn't want to get it, because they were not good enough targets for monoclonal antibodies and disease.


ZIERLER: What would a "good enough" target look like? What would that mean?


AMZEL: A good enough target depending on the antibody and many things, and there are many treatments now. A good enough target would be, for example, an antigen which shows up only in cancer cells. That's a good enough target.




AMZEL: And is responsive to T cells if the antibody recognizes it. With those two conditions, it's a perfect target. For cancer. For other diseases, it's similar. Because now they are not only for cancer, they are for many diseases.




AMZEL: If, if we put on the TV, well, not this one because this is public TV only, put it and look for the mab at the end of the name and see how many... how many antibodies are being used.


ZIERLER: So it sounds like when you got to Hopkins, you were working much in, in biology than you had been previously.


AMZEL: Oh, yes. Oh, yes. Oh, yes.


ZIERLER: Now I know you took, as an undergraduate you took some biology classes, but were you learning biology essentially on the fly when you got to Hopkins?


AMZEL: No, more than anything else-- No. More than anything else, I knew biochemistry, and I still know a little bit. So the biology I only learned on the side, and is only, only cell biology.




AMZEL: If you tell me, tell me other functions of the pancreas besides producing insulin, I will know very little.


ZIERLER: Yeah, yeah.


AMZEL: Simple... and the same will be true for any organ. (laughs)


ZIERLER: Uh-huh, uh-huh. So at what point--


AMZEL: But you know, if you tell me, tell me what happens to nitrogen?




AMZEL: If you give me, let's say, half an hour, when you get a nitrogen compound, I can tell you this.


ZIERLER: Okay. (laughs) And at what point do you move on to the tenure track at Hopkins? How long are you a post doc and then when do you move into the assistant professor track?


AMZEL: Okay, let me... That was why I got the computer.


ZIERLER: While you look that up... Dr. Amzel. Dr. Amzel, while you look that up, if you don't mind, let’s take a brief break.


AMZEL: Yes, yes, yes.




AMZEL: Okay, so I have the information here, but I can give you this. In the University Central in Venezuela, our faculty positions were Instructor.




AMZEL: But those are faculty position, non-tenure.


ZIERLER: Right. But you were still a graduate student there, you didn't actually move into--


AMZEL: That's correct, but remember that they (ZIERLER: Differences--) did not have, okay, the system allowed people with only undergraduate to be instructors. Because people that wanted a doctorate had to go abroad, because there was no doctorate in chemistry or physics, or... Okay. So then, I did a few things for Organization of American State, and then I became Instructor in Biophysics at Hopkins and in 1973, they made me an assistant professor in the medical school, that's tenure track.


ZIERLER: 1973? So--




ZIERLER: But in 1969, you were already instructor? Or that was another promotion from post doc? Meaning, in 1969, when you came there, were you instructor right, right away?


AMZEL: Instructor... in biophysics... No, I was a postdoc.   I became instructor in 1970.


ZIERLER: Okay. Okay.


AMZEL: And then so. '69 to '70, I was a postdoc. '70... I didn't put the month because the margins of this CV doesn't allow it. And then I remain until 1973, when I became an assistant professor, and associate professor in '78. And a full professor, which at that moment is tenured. The tenure goes the... automatically with full professor. In 1984.


ZIERLER: Now, when you became assistant professor, did you change affiliations, or you were still in the same department?


AMZEL: No, I was in the same department, yes.


ZIERLER: Now, being affiliated with the hospital, were you dealing with patients?


AMZEL: No, that story I would recommend not to get into, (laughs) because the affiliation of the medical school with the hospital changed over these years. The, they were a single institution.




AMZEL: But it wasn't working. Some aspects of it-- You know, I don't know. So then they made it two associated institutions, but there is Johns Hopkins Hospital and Johns Hopkins Medical School. That both together are Johns Hopkins Medical Institutions.




AMZEL: The dean is the dean of the medical school, and the dean CEO of the medical institutions. And those things happened in just this time, so I really don't even know which one is my (both laugh), my institution.  I am in the Medical School.


ZIERLER: Uh-huh. And so what were the circumstances that led to you getting on the tenure track? It was just that you were doing good work, and they offered this to you?


AMZEL: Well, they, yes, they...


ZIERLER: Meaning, this was your intention--?


AMZEL: Antibody, antibody work, the Fab work, was really high impact.


ZIERLER: Yeah. And how did you know it was high impact? What was the feedback mechanism that you knew it was high impact?


AMZEL: Well, I mean, all, all the things that are now automatic didn't exist, but you know, people asking you to write reviews, the people commenting on your place, the number of papers that were using that information for other things. There were ways to evaluate it without the impact factor of a journal.




AMZEL: And the number of quotes. So it was clearly very, very high impact. It was the first structure that allowed people to know how antibody recognize antigens. So that was high impact, and then, you know, I have to come up with my own projects, so I started to work on another thing that also have high, you know, it was very interactive with thermodynamics, and that is ATP production. So there was a person at Hopkins that was working on the mitochondria ATP synthase, and I took that as a project, so more than anything else, what I was thinking is, you know, to have some time to, to think and to work on a project besides the fact that I could use, you know, knowing more thermodynamic that most people that do structure, if I center on structures, which are very big, there would be less competition. So this was a big structure, good thermodynamics. And a person at Hopkins that could help me with the preps.


ZIERLER: How much teaching were you doing at this time?


AMZEL: A reasonable amount. I was teaching probably about six to eight lectures in a graduate course that was... the last name it had, had many names over the years, biophys-- biochemical and biophysical principles, and then I taught a course in computer modeling of biological macromolecules, and that was it. The other course I taught, again, like ten classes and directed the-- I directed both courses, but in one I taught about six to eight classes, and the other eight to ten.


ZIERLER: All graduate classes?




ZIERLER: Never taught undergraduate?


AMZEL: We do not... We very, very seldom in the department teaches undergrads. They have some people now that are doing a few classes. We teach medical students.




AMZEL: But I chose not to do that and concentrate on the graduate classes.


ZIERLER: Right. So your graduate classes were mostly medical students, or, or not?


AMZEL: No, no. PhD students.


ZIERLER: PhD students.


AMZEL: Masters and PhD-- all in the PhDs.


ZIERLER: Uh-huh. Now, at this time, were you focused on a particular area of human health? At what point did you develop, you know, particular interests in, in cancer research? And inflammation and things like that? How did you decide what to focus your efforts on?


AMZEL: Well, the, the first thing wa-- the thing with the, with the ATPase, the mitochondrial ATPase, it's, it's interesting. It was, you know, as I expected, a high profile thing. But nobody got into it until a few years later, and the person that got into it was a person from Cambridge called John Walker,  I tried to be unnoticed, but he just took it further than I had, to be the person in the subject and actually misquoted me, and did a few things that he shouldn't have done. So I finished my work on that, and he got the Nobel Prize.. And I mean, it's fine with me. But not everything that happened there was clean.


ZIERLER: Uh-huh.


AMZEL: And that--


ZIERLER: Did you think about leaving Hopkins?


AMZEL: No, no, no.




AMZEL: As I, as I said, unnoticed is good for me.


ZIERLER: (laughs)


AMZEL: So, so no, I mean that's it. I, I published what I had to publish, I said what I had to say, you know? Because people jump on the bandwagon, it was not a good... moment for me to try to, to do anything else, so I... I left the subject. And no, and I followed the literature. If somebody from Hopkins is involved, it helps me more. And one thing that--


ZIERLER: Why is that? Why does that help you more if someone from Hopkins is involved?


AMZEL: Because, you know, if I, if I'm preparing the protein and I'm having trouble or whatever, they can send, I can send somebody from my lab there without having to be a big deal or whatever. So in the intervening time to the major project I'm doing now, I had several projects that were related to subjects which I follow all the conditions. They had good thermodynamics, they were large proteins, and I had good enough interactions that if I got into trouble, I had a good contact. Every time I did that, I offer the person that was covering me had the biochemistry or the cell biology of the subject to be a partner and I respected that, so if you see most of my papers have somebody which is the owners of the subject.




AMZEL: Or participate in the ownership of the subject. So two or three things that come to mind at this moment are lipoxygenase (collaboration with Dr. Betty Gaffney), which already had a, a very strong health implication. The only enzyme that had been purified and probably still is, of the lipoxygenases, is the one from, from a plant:. Soybean. But the human one is the one involved in the synthesis of leukotrienes and lipoxins, which were the target of most of the pharmaceutical industry. So I chose to work on that one to provide the main structure for the pharmaceutical industry, to have a target. At the end, the pharmaceutical industry became less interested. They're interested again now. But we were the ones to first publish that structure. And the pharmaceutical industry used it a lot, although I don't think any of the compounds that I developed were eventually used. Two more proteins, one is the, related to response to redox compounds, which is extremely important for a very large number of medications, so how do we trigger the response? And we did the structure of that one. And we did the specificity on many things. The third one in that group is one of the large proteins, which is involved in axon guidance. It's not the most important protein to axon guidance now, but at the time was one of the proteins identified in other processes. We are still working on that protein, but at, at a lower level.. And then during all that time, I was following many things, and I found a paper from Bert Vogelstein's group, in which they indicated that one of the enzymes that is heavily mutated in tumors was the PI3Kalpha. So--


ZIERLER: In all kinds of tumors?


AMZEL: They identified at that moment in five kind of tumors, but now it is in many more.




AMZEL: So, I call him, and he agreed to collaborate. So they had the clone.


ZIERLER: And what year would this have been? This collaboration?


AMZEL: The paper, paper was in 2004, so that was probably was just as the paper came out.




AMZEL: So we started working on that enzyme in 2004, and when did we publish the first paper? Let me see. Should have been 2007. It took us a long time, and it wasn't easy. And, and at that moment, we were full fledged into human health, because the first thing is, how do the mutations favor the cancer cells? Why does the cancer accumulate these mutations?


ZIERLER: Right, right.


AMZEL: You realize that when people say these kind of things, there are many things that they don't know. And they don't try to hide it; may be too complicated to tell the story if you try to do it differently.




AMZEL: Which is, do a single cell has more than one mutation? Nobody knows. There are no good studies.


ZIERLER: Nobody knew then and today?


AMZEL: Probably not even today, that nobody sequence single cells. Maybe they did, I don't know it. But then, nobody knew.




AMZEL: So. What is it? If different clones have one mutation, and that's enough to make that clone prevalent? Or not even that. They don't even know if the clone that has this mutation is 5% of the clones, 1% of the clones, or 30% of the-- of the cells. Or 30% of the cells.




AMZEL: They don't know so many things. But at least, it was very clear, well. One thing, it was clear to them as it was to us, is that having these mutations interrupted, or allowed some pathways that allowed cell motility. That allow cell survival. That diminish cell death. That make the cell more resistant to some things. All those things are activated if this enzyme is activated. Now, that's why it is one of the major pathways. So it was clear that this, it is activated, now. Why, how do the mutations activate the enzyme? How is the key question for us. And we determined that these mutations activate the enzyme by favoring conformations that are present only on the activated enzyme. The story is quite elaborate by now, but that is the bottom line. These mutations favor confirmations that are activated, they are only prevalent, or they are only significant we'd say, in the activated enzyme. So is a fake activation.


ZIERLER: Now, I want to ask, in these early years, you're asking these fundamental questions about how cancer works.




ZIERLER: Intellectually, are you looking at this holistically in the sense that if you find the right answers to your question, there might be global therapies for cancer? Or are you looking at it very narrowly, saying you understand how complex cancer is, and we're looking to make a discovery in this relatively narrow field and that may or may not have benefits beyond what it is that we're looking at? How, how wide is your, is your panorama?


AMZEL: That-- That's a very, that's a very good question. I keep on asking myself, am I close to have an answer to one of the other questions I told you, that everybody has?




AMZEL: And it didn't happen. With the thing of doing, my first answer will say, "No." I work on these systems and this is what I want to know: how it works. This will be the goal of my life, I can die in comfort if I get it. And, but it is not true. At the end of a paper, I say, "This kind of mechanism may, may be happening in many other situations. So I cannot believe that it happens only once in the history of evolution. That it will never show up again.




AMZEL: So, so the fact that you can have a structure, and activate-- an activating mechanism that makes some structures active, and that has an effect if a cancer cell has it. But you can have another modification which is nearer, not even in this side, that also produce an increase in the population, which makes it good for a cancer cell, that that will not happen in another system. So I think it will. I think it is happening in other systems.


ZIERLER: But you're still not sure?


AMZEL: Probably I am, but I don't write about things I don't work on.




AMZEL: So if I would say, if I look at other people's data, this may be true in their system, I don't do that.




AMZEL: Because you know, it's their data, it's infringing, it's not what I do.


ZIERLER: Yeah. If you look at, I'm thinking--


AMZEL: You think this guy is crazy, he has too many hang-ups, but you know, they keep me sane...


ZIERLER: Were you thinking in the 1970s, I'm thinking about President Nixon's announcement in 1972 about the, the war on cancer, right?




ZIERLER: It seems that there was an idea in those early days that there were global therapeutic solutions that would really make, you know, the idea of a war means that a war can be won.


AMZEL: Yeah.


ZIERLER: That, that cancer is something that can be eradicated. Were those... I mean, how, how did you respond to those, to those kinds of ideas? Did you see, at least in those early years, that cancer was something that could be eradicated? Or did even then, did that seem to be a naïve concept to you?


AMZEL: You know, I wasn't thinking that hard on that, but my impression is that even at that time, there were enough people around me that said, "Cancer is not a disease."


ZIERLER: It's not a disease.


AMZEL: Correct, it's not a disease, it's a series of different things that go wrong with each individual cancer type, and maybe with each individual tumor.


ZIERLER: You mean it's not a single disease, it's many different kinds of diseases?


AMZEL: Correct, correct. Correct.


ZIERLER: Right. Right. And so if you recognized the complexity, how did you go about in this universe of complexity that is cancer, how did you choose what areas to focus on?


AMZEL: Well, you can get more or less an idea because I also only do what I know how to do. I'm not going to stain cells with red and orange and look at the microscope. I'm not going to do that.




AMZEL: I could do it but there are people who are ten times better than I am, why am I going to get into that? So, I had to look at all these things, but at the same time things where I think I could contribute at the end. And just to get something that could be related to that. As, for example, when I said we work on the enzyme that is involved in triggering the response to redox compounds. Many of the anti-cancer drugs are redox compounds. Or several-- no, many. So I'm not doing directly anything related to cancer, but it is related to cancer. If somebody could stop the redox compounds when giving a redox compound against a cancer cell, it would increase the effect on the cell. No?




AMZEL: Maybe they are doing that now, I don't, I don't follow it enough. So many things are indirect hits. (ZIERLER: Yeah.) But--


ZIERLER: "Indirect" means you, you don't know what it is that you're gonna find?


AMZEL: All... It was something that it will get me, well, it will get the field in a direction where it could go. Well, and the most direct one was, was the thing with Bert Vogelstein. And we are still working on that. So and we are doing very well, really doing everything we know.  So that's doing, I consider, well. And then in the meantime, the things that you see now we also started working on the voltage-gated sodium channels. That's a very old project. Again, time to look at things that had to do with health. There was a very good group in cardiology (Eduardo Marban; Tomaselli) that was working on sodium channels. It was very, very early in the game. And there are many cardiology-based detected mutations in these channels. The main spike on the EKG, is given by these proteins. We were interested in knowing, you know, what interventions one can do to the people that have cardiopathies which are based on a mutation. And there are, there are hundreds of mutations. Ah--


ZIERLER: In the heart?


AMZEL: Sorry?


ZIERLER: In the heart? Mutations in the heart?


AMZEL: In the protein of the heart, yes. I mean, there are many others which are other things of the heart. Shape, size, but these are just one protein of the heart.


ZIERLER: But these mutations do not manifest as cancer?


AMZEL: No, no, no. These are mutations that they were the way they manifest is cardiopathics.


ZIERLER: There's no such thing as heart cancer, is there?


AMZEL: That's interesting.  At least they are very rare..


ZIERLER: Why would that be?


AMZEL: I don't know, I don't know.


ZIERLER: Right? You never heard of heart cancer.


AMZEL: No, I didn't. No, no.


ZIERLER: I mean, every other organ in the body.


AMZEL: And, yeah, that's true. I haven't heard of heart cancer. We'll check it later. So, so because this is an integral membrane protein, is a channel, and at that moment, membrane proteins of that size were very, very difficult to handle, we decided to work on the cytoplasmic portion, which is about 200 amino acids, and dealing with it as a soluble protein. And we did that, but it took us over ten years to get a good sample. Not working the whole time at it, and eventually we got a good sample, and eventually we realized that other people had researched there concentrating in the cytoplasmic portion interaction with calmodulin. And that a lot of the regulation initiated by the cytoplasmic portion was carried out by calmodulin and calcium. And we are in the middle of that, we published a really nice paper on that. And we are continuing. One thing we are doing, which is directly clinical, but we are not going to do the clinics, is when it's one mutation, which is in a place where we think that if you mutate calmodulin, if you mutate calmodulin and transfect calmodulin to a patient at a low level, this transfected calmodulin could make the mutated channel work correctly.


ZIERLER: Which would, which would tell you what?


AMZEL: Will cure the disease.


ZIERLER: Ah-huh.


AMZEL: Everything is built on conjectures, okay? Because we still don't have the mutant calmodulin. But we are working seriously on, on getting the mutant. Calmodulin is such a basic protein that maybe even making one mutation in calmodulin to make it work the way we want it will kill the patient.




AMZEL: For that, we have to do many difficult tests, and for that we need collaborators. I don't do animals. Well, first in cells that carry the mutation and see if we can correct the effect of the mutation in cells. And then can we correct it in mice. And then we'll be allowed to correct it in humans, no? But that will be a direct intervention, and we are not doing that at tis stage. Can we design a mutation in calmodulin, which will correct the S1904L mutation, which leads to Brugada syndrome.  Brugada syndrome is an EKG-detected mild cardiopathy, but some people are OK, and some people suffer.


ZIERLER: With heart attacks?


AMZEL: Yes. I th-- Yes, yes, heart attacks. Yes.


ZIERLER: What's the exact therapy? I mean, what's the, what's the transition from making this discovery to this being a therapy for patients?


AMZEL: Well, the sequence is what I said. We first have to show that the cell that has the mutation, if we put, if we over-express our calmodulin, the triggering is normal. So we can overcome the mutation. If that is true, then we have to show that for those cells and others, having the mutated calmodulin doesn't produce any disruption, you know? You dissolve your muscles. (laughs) Calmodulin is everywhere. You have something, you know. Then, if that doesn't happen in other cells, then we have to try it in mice. Are the mice normal? What things do you check? If the mice end up normal, then there will be many test for that, then one can ask permission to test it in humans without the syndrome and with humans with the syndrome. So it's a long way.


ZIERLER: I want to return to, you were talking before about discoveries that you had made that had pharmaceutical impacts.




ZIERLER: How did you liaise with the pharmaceutical companies? Were there scientists at the pharmaceutical companies that you were in contact with? Did you attend conferences? How did you get, how did you work with the pharmaceutical companies?


AMZEL: Well, at this moment, I'm not doing that, so--


ZIERLER: Currently.


AMZEL: Currently. And that's for some time. I don't remember the year, but at some moment, I was in contact with, and you realized more or less what the year was, because the company was called SmithKline Beecham, and I was in contact with them, and I interacted-- I had meetings with them. But then when we wanted to exchange compounds, it became so difficult with the Hopkins constraints, and with the company constraints, that I spent a year trying to do it and it didn't work. And I said forget it, I can do things which are more interesting than this. Probably if I go now, it will be extremely more easy, but I never went back. Again, I have many hangups, and this is one of them, and I stopped at the time and never did it again.


ZIERLER: You never got involved with drug making again?


AMZEL: Not in my sense. I, I write it in my paper. This is a good target, or this could be...




AMZEL: But I do not contact the companies.


ZIERLER: Do you see that your research is picked up by the companies?


AMZEL: Oh, yes. I mean, we published one construct for... Sorry, the PI3K. The construct is very unique, no? We publish it. The companies did not ask us for our DNA, because synthesizing the DNA costs $500. But then they are now 30, 40 structures that come from companies that were done with our construct and their compounds. So I know that they are using it. I mean you, we can check it now and I can, I can show you. I mean, there is no doubt.


ZIERLER: Right. Would you say that most of the areas of research that you've pursued are open and closed, or are they mostly ongoing? In other words, in a very long career, right? In any given time, you're working on however many projects you're working on. And over the decades, are those projects, do, do they sort of continue on, or do you usually close a given project before you start another project?


AMZEL: No. I don't necessarily close all the projects, but the question I ask at every... very frequently, very frequently, especially when I have one result and I am thinking, what is my message here? Is there anything which is useful and important that I can continue starting now? And sometimes the answer is yes. And sometimes the answer is, this is the time for other people to intervene. The people that do the orange and the green stains, the people that inject the mice, and for me, the things I can contribute are not going to be as important as those, and is a good moment for me to stop.


ZIERLER: So you're going to define your involvement in a project strictly within the parameters of what you see yourself as being good at?


AMZEL: Absolutely, absolutely.




AMZEL: Yeah.


ZIERLER: And so once you've made that determination, right, how do you define, in terms of determining how much of your resources and time to put into a given project, how do you determine success versus failure at the beginning? In other words, right, there are so many things that you could be working on. When do you know, like, what are the things where it tells you, "This is, I'm on to something here. I'm gonna continue with this." Versus, "I see that this is going to be a dead end, and let me, let me stop and go on, go on to something else." How do you, how do you determine those parameters?


AMZEL: Well, I'll give you an example, because they, they are not, I mean, they are not absolute things. But for example, I'm not working on lipoxygenase.


ZIERLER: Currently?


AMZEL: Currently. So, I did structure of lipoxygenase. I knew at the time that the industry was interested. I knew that they used the coordinates. So I did, complexes were not possible because the solubility of a substrate is very low, and the affinity for the substrate by the enzyme is not great, so there is, you can soak anything you want, but you never see a substrate bound to the enzyme. Industry as, as well as I, were interested in the human. Because of the homology, we thought that we could have a very good model of the human. Without a structure of a substrate or a substrate analog, there were some small molecules that maybe we could bind, but were not big enough to, to guide the substrate binding. What was left about the mechanism was really ion organic chemistry, which I don't do. So. Published the model of the human, and that's all what I can do. There is nothing else... Why would I continue spending time and doing something that I cannot do?


ZIERLER: But does that mean that you closed the project, or you hand (AMZEL: Yes.) it off to someone else who can continue in a different area?


AMZEL: My collaborator, Betty Gaffney, continued working with EPR and had a review this year.  I never talk to anybody else, but I'm sure that the history I followed for a little while, is that the industry decided, the protein, to be able to have access to the substrate, associates with the membrane, through the membrane, through a membrane associating protein. And industry decided that it was much easier to deal with a membrane associating protein than with the lipoxygenase, itself. And they went in that direction for some effort. After that, I didn't follow it anymore.


ZIERLER: Uh-huh. Do you see yourself as a specialist or a generalist?


AMZEL: Well, that's a good question. No, I think because I look for the relation to first principles, I'm a generalist, not a specialist, yes.


ZIERLER: What is it about first principles that makes you go in that direction?


AMZEL: That's the only way I think I understand.




AMZEL: When somebody makes me a PowerPoint drawing of these things binding to this, and this thing being released and binding to this. To me, is a sequence of events, is not understanding, is a phenomenological description. If on the other hand, you can say, "When the things are at this level, this is either a steady state or this is an equilibrium state." In e-- suppose that it's an equilibrium state. In this equilibrium state, I can define, for example, these eight species. Of these eight species, I know the structures. And I also know the populations because I have thermodynamic measurements, so I can tell, to go from here to here, the most likely event is to go from this population to this population to this population.


ZIERLER: Yeah. So does that mean, again in terms of how you think of yourself, do you see yourself primarily as a physicist working in biological systems?


AMZEL: Yeah, the thing is that I am a chemist and--


ZIERLER: You're a chemist.


AMZEL: At the end, yes.


ZIERLER: But you, but it sound-- you're a chemist, but you bring a physics--


AMZEL: This is a physics background (ZIERLER: Framework), because of thermodynamics. But you have to realize that all the people that do chemical thermodynamics are chemists. But is, is a physicist view, yes. But you know, physicists are people that consider themselves the people that, do general relativity, those are--


ZIERLER: Of course. Right.


AMZEL: String theories, I am not one of them.


ZIERLER: Yeah, yeah. But, I mean, thermodynamics is real physics.


AMZEL: Yes, it's real physics, there is no doubt, yes.


ZIERLER: So what are the fundamental principles of thermodynamics that inform everything that you do and the way that you understand problems? What are those fundamental principles of thermodynamics?


AMZEL: Well, they are the three, four laws, and that's so obvious that, I mean, they're always there, you don't have to... You don't have to look for them.


ZIERLER: But can you explain how you get them?


AMZEL: No, I was going to, I was going somewhere.




AMZEL: And then it came Gibbs. So the idea that you can relate energetics of populations to the three principles of thermodynamics, is one of the major things that happen in science. So, so is the Boltzmann equation with the Gibbs extension, if you want to do it for free energies just with the Gibbs extension, let's say, that makes it being so important. If you don't use statistical thermodynamics, thermodynamics is just another things that should happen. Well, you know, if there is gravity, this thing will fall.


ZIERLER: So statistics is what gives it an application.


AMZEL: Statistical thermodynamics.




AMZEL: Yes. And this is to make it independent, that's why I say Boltzmann and Gibbs. Of statistical mechanics. Is not that I have, be able to calculate the thermodynamics from the molecular motions. They are wiser things that, you have, you can calculate it for example for the populations of, of states, and one state could be the protein with the substrate in a pre-catalytic conformation. You don't know the molecular motions, you don't know the details. You are not doing the-- so it's not molecular mechanics at that level, it's statistical thermodynamics, no?


ZIERLER: Yeah. Do you see the way that physicists talk about a unified theory in physics, right?


AMZEL: Oh wow, I don't think...


ZIERLER: Do you see a unified theory in biology? Is there, are there, you know, mysteries of biology that if they can be understood, can unlock all of the mysteries of how life works?


AMZEL: Well, there is in biology itself, although if you take off the things, the kind of things I do, the only theory is evolution.


ZIERLER: The only theory is evolution?


AMZEL: Is evolution. For the moment, the only theory is evolution, so the problem is that evolution is, you know, such a statistical thing that it's not very conducive to mechanisms. you know, at the end it's... So I--


ZIERLER: Is that a problem for the theory?


AMZEL: I think so. But in general, for example, one thing which I tell people and they look at me, is this guy crazy or no? For example, people are now very interested in machine learning, people are very interested in information theory, no? People are interested in all the things that are happening now in neural networks. And big data. I think that some people think that those will provide what scientists are looking for. Conceptual frameworks they are not.


ZIERLER: That may move us beyond evolution, or may improve our understanding of evolution?


AMZEL: Because we really don't know what the theory is, so both, let's say.




AMZEL: They are wrong. There is no conceptual platform that will take us from machine learning, big data, neural networks, to anything which is a principle.


ZIERLER: Why not?


AMZEL: Because the only thing they do is give statistics. And principles do not rely on statistics. They are always true.


ZIERLER: You sound like a physicist.


AMZEL: (laughs) No, but I mean, it has to be. I mean, it's another way of looking at the world. I mean very useful. Machine learning, all those things are useful. I'm using it ß, you know, to, to guide my thinking. But that's not a principle.




AMZEL: So if in biology there is a principle, it should be a principle. These things work this way always. Not 84% of the data say.


ZIERLER: Do you think that the distinctions between physics and chemistry and biology are essentially artificial? That those are really constructs of how the human mind works? And that there are in fact greater connections between these disciplines than the way that we tend to think about them?


AMZEL: I think so, I think that yeah. In the end, for something I'm going to become philosophical, philosophy of science. And I think that at the end, they are the same thing, but the connection is the scale.


ZIERLER: The scale?


AMZEL: Is the scale of observation. If you look with a light microscope, you have a scale of observation and it's not that you're ignoring physics. You are using it for the lens, you are using it for the light, you are using it for the laser. You are using the physics for the fluorescent compound. But for the scale that we call "biological" we are only observing things that cannot be directly related to first principles. We try very hard.


ZIERLER: Why can't they be related to first principles?


AMZEL: Well, in some cases they could. For example, if you are looking at the relation be-- between cells... membrane deformation and membrane potential. You can write equations for everything. There are so many parameters, even if there are not too many, there are so many that are heuristic that create a difference between that and physics. The same thing I saw that on physics. About physics. For example, a liquid flow. Fluid-- fluid dynamics. Fluid dynamics is not at the same level as mechanics. Or is not on the same level as thermodynamics. So the observations in biology are closer to observations and things that we do in fluid dynamics than what we consider first principles. I realized that I'm pushing the envelope here, but...


ZIERLER: And where does chemistry fit in this?


AMZEL: Sorry?


ZIERLER: Observationally, where does chemistry fit in this? You're contrasting observations of scale from biology and physics. Where is chemistry in this?


AMZEL: Well, chemistry has many more places where it touches physics because there is quantum mechanics. Which is, you know, highly detailed physics and very mathematical physics. It also has the determination of compounds, analytical chemistry. It has synthetic chemistry, which in many cases is experience plus physics. And the same is that at the level that it is used, it is over parametric, uh, and I put "parametric" in quotes, you know, the way people think. And the way people come up with solutions. It separates it very well as a field in itself, yes. But I would agree that they are all the same field, yes.


ZIERLER: Yeah. I wonder if you could reflect on the, the, the contributions of crystallography in general in advancing science. What, you know, we're talking in the context of your membership as a distinguished member of the ACA. What is it that crystallographers or crystallography... what is it that they contribute to human understanding of the, of the natural world?


AMZEL: Well, no, crystallography was very, very impressive, no? For example, I mention one name I mentioned before. What was Galoni's degree? He was a geologist. No?


ZIERLER: Yeah. Yeah.


AMZEL: So geology, many structures of rocks you can do by first principles. That's just knowing the chemicals. Most of the structures of rocks, I mean thousands, were done crystallographically. So geology, I mean I imagine, I am not a geologist, but I imagine that they are completely grateful to crystallography to, to make their day, no?




AMZEL: Then it came chemistry. Compounds. And then Pasteur’s observation of tartrate crystals, that the idea that there is asymmetry in compounds (chirality). I mean, and that's, and that's as fundamental to chemistry than it is to know that there are bonds, or the periodic table. Not having-- it's true. And then, for I would say half a century and still now, every new compound that is done, the structure is done. So we know the structure of almost every small molecule that we are making. So chemistry owes its life to crystallography. And then we started biochemistry. And then we started to look at proteins. It started with proteins being, those amorphous substances that when they get isolated they may gel, to having a structure, and then with the unique technique, which is crystallography, we are determining the structure of every single protein we are interested in. All our, almost, of what we can say about them or what we expect to say about them, comes from looking at the structure.


ZIERLER: What do you see as crystallography's role in the future looking ahead? What can it continue to contribute to science?


AMZEL: Well, one of the things is something I'm doing and I cannot not say. The structure of the membrane portion of a sodium channel, it was sodium channels came out by cryoEM. Many came out all at once. But the cytoplasmic portion is disordered. We had the structure of that portion and we and other groups, our ten, 12 structures of different combinations of that portion of the structure, we'd come out with it. That's done crystallographically. High resolution, or higher resolution, and that allows to indicate what structures could be controlling from the cytoplasm, which is where the control should be, could be controlling the behavior of a channel. So at this moment, 3.6 Å resolution structures with many parts invisible, is contributing a lot, but not everything that's needed. Eventually, my impression is that many of the structures will have to be determined crystallographically and will have to be combined, combined with EM structures, and that will be where we are going to look for the answers. Some people are going to go for the broad answers, some people are going to go for the very detailed answers. All of those are needed and the detailed answers probably will need crystallography.


ZIERLER: Now, to go back to your department.




ZIERLER: The field of biophysics.




ZIERLER: When you started your career, how developed was this concept of biophysics? Did you know the term "biophysics" before you got to Hopkins?


AMZEL: Probably not.




AMZEL: So at that moment was a beginning word. Hopkins was one of the first biophysics departments in a Medical School.


ZIERLER: Yeah, right. And do you know how it started? Was it, was it a break away from the physics department or was it a break away from the biology department?


AMZEL: I'm not completely sure, but my impression is that a scientist called Howard Dintzis was working at Harvard, and he came up with the direction of the expression of  proteins: proteins were expressed from the N-terminus to the C terminus. And other things which were important about the ribosome. And my impression was that he was making a lot of friends, let's say, on the idea that the... it was a good moment to start to interest people in studying the ribosome. For things with the biophysics at the time, the ultracentrifuge was coming along at that time. And negative stain EM was coming at that time. And my impression is that they offer the chairmanship to Howard to create the department. With our-- without splitting from anything and he could choose the people.


ZIERLER: So it was a new department entirely?


AMZEL: New department entirely, that's my impression. But I never had a real, real description of the story. Probably I'm not very wrong. Probably I'm not very wrong.


ZIERLER: So when you joined Hopkins, was your sense... It's still a merging of two disciplines, and if it's a new discipline, the people working there are coming from one or the other, by definition. They're not coming from the joint, because it doesn't exist before. So was your sense at Hopkins that the biophysics department were biologists who had a physics background, like you, or were it, were they physicists working in biology?


AMZEL: Wow, that's interesting. I think it's the, the second one, but some of them had been already through some biological or biochemical... I don't remember all their names, but I remember most of the people. I think if we looked them up, they would not be around, because they are one generation older than I am.


ZIERLER: Yeah. So I guess the question is, did you see it primarily as a place where biology was being done with a background in physics or was it a place where physics was being done with a background in biology?


AMZEL: No, probably biology was being done with a background of physics, yes.


ZIERLER: Okay. So you fit in well--


AMZEL: Because for example, one of the persons that was there in the department, he was trying to decipher the chemical structure of the cap of bacterial RNA. So I would say he was somebody that was using in this case a chemical background to study a very, very chemical, biological question, yeah.


ZIERLER: And how has the field changed over the years? How has biophysics changed from those early years? Or I should say, what has remained the same and what has changed?


AMZEL: I think that what has changed is that some of the techniques that one person could make a career out of knowing one technique.


ZIERLER: Nowadays. Or in the early days?


AMZEL: No, in, that used to be.


ZIERLER: That used to be, okay.


AMZEL: For example, if you... if you did ultracentrifuge.




AMZEL: You could do a career on ultracentrifuge. If you were doing, how is it called? Fluorescent quenching to look at the fluidity of membranes. You could build a career doing that. Those things are gone.


ZIERLER: You can't be a hyperspecialist anymore?




ZIERLER: Why not?


AMZEL: Because the techniques became now so simple to run that people will run them as part of a global inquire.


ZIERLER: Uh-huh.


AMZEL: They will be people that do all those things without knowing as much as the other people knew, because it doesn't matter because with computer software, you can see the answer.


ZIERLER: Right, right.


AMZEL: So what is left, well, I'll tell you the way I thought 13 years ago when we, they told me, "Do you want to be a chairman?" And I said no. And they said, "Well. I mean, think what you can do as a chairman." So I did. And I thought about this question, no?




AMZEL: So single cell/single molecule. People are still developing their techniques. The techniques that microscope could turn better and better. While the people are better and better at doing things with them. Which are not the same stuff. So that would be something that in the next ten years would still be a valued field. Ten years has passed, I have a extraordinary group, I probably have the best group in the country, of people doing single cell/single molecule. And they are still doing science that goes to the prime journals. The other thing, and this was a guess, was a good guess, but guesses like this could be very bad. We brought people to give seminars, and when people that were doing things that involved electron microscopy mentioned that the detectors for direct detection of the electrons were coming along, and that would allow to take movies of unstained samples-- EM photographs. That was enough for me, and I said, "We have to start this." Because probably most of the problems that people are having now getting single molecule structures from EM comes from the detectors because of distortions and because you are doing it through a screen. And a screen, a fluorescent screen. So that cannot be good. So I said cryo EM was my second choice. Then, step up physical chemistry, that I always wanted in the department no matter what. And the third one was motions. And for motions, I did not foresee that maybe microscopy could get that from multiple structures, but the only technique that would be good for motions would be NMR. And maybe we can capture one of the people that are doing motions through NMR. So that for us is Dominique Frueh, who was doing that. So that's the way I thought at the time. I probably did not change my mind yet. That those are the, the things. No, and of course. Those are the things that have to do with biophysics. Many of the new optical techniques, the things with the sheet in which they go... I don't even know because I don't follow them. The things that the microscopists are doing for just discovery observations are really impressive. But I don't know enough.


ZIERLER: I wanna ask, I think three final questions for our interview. First, in looking back at your career. What are some of the failures you experienced, things that were clearly, you know, in however you define the word, it just didn't work out. What are some of the big standouts in your career that you see as failures or shortcomings?


AMZEL: The ones I'm going to tell will not look very impressive. (ZIERLER: That's why I'm asking first.) But is the biggest failure. When I was looking for a subject, after the immunoglobulins, I was going to continue in the path of binding. I was not going to be competing with Roberto, of course. Oh, in the meantime of that, there was the Paris thing, which I did not mention. Complicated story, but I was going to go to Paris with Roberto, but then I didn't go, mainly for family reasons. This has--


ZIERLER: For a fellowship or to go over permanently?


AMZEL: No, no, no. I had a position there, yes. But this has something to do with fa-- family, with my divorce, is too, (ZIERLER: Too complicated.) too complicated, so I shouldn't, I shouldn't bring it up. The thing I was, I knew very little biology. So one thing that I knew that was important in biology and was probably easier in biology than medicine, was food production. So I looked at it seriously, on food production. I settled on a protein called phytochrome. Phytochrome is a protein that has a prosthetic group that has two states. And the two states are triggered by light, red and blue. And I will make a mistake now if I try to say which one is which one. When phytochrome gets one of the lights, it goes into a state that relays some signals, that when it gets the other light now, it has a state that has a half-life of about four hours, five hours, depending on the temperature. And then it will get to the other state, after that time, and on that state, it triggers something. So in principle, as it was known at the time, and I just, don't know if it's due to, a control that tells plants to drop their leaves, flower, tell when the fruit has to start. And it did all this through a quantum mechanical transition between two stable quantum mechanical states. Imagine, from where I came, that protein was everything I wanted in my life. And there was a guy that worked in the agriculture department north of Washington, in one of the buildings they had. And he had the protein. So I spent one year going to that place. Because it had to be with green light, because otherwise you get a mixture. If you had real light, you get a mixture of forms. Trying to crystallize it. One year, going half a day every week, and I didn't. I think the protein has been crystallized now. It doesn't have all that functions. I, I just dropped it. And I considered it a big failure, I considered it a big failure.


ZIERLER: Because of all the time you invested into it?


AMZEL: No, because I thought that I could do a lot if I had that structure.


ZIERLER: Uh-huh. And so what was it really? Was a lack of understanding?


AMZEL: No, no. It was very difficult. I don't remember how they crystallized it now, but it was a, it was very smart, yes. At that time, not enough was known. And you know, we didn't even know if it was a good enough protein.  As with other projects, I was trying too early.


ZIERLER: All right, now I'll flip the question.


AMZEL: Sorry?


ZIERLER: I'll flip the question.




ZIERLER: Some of your major successes. Things that you have discovered that have significantly moved the ball forward in human health research.


AMZEL: Well, PI3K for sure. Well, Fab. for sure. I mean, the Fab., the first thing I did as a post doc. That was sure, that was the probably highest impact ever.


ZIERLER: Now, "impact" by citations. But how do you know... I guess my question with "impact" is, how do you know when it's not just a bunch of scientists who are citing each other? You have to break out of that.


AMZEL: Well, no, that's why I'm saying it now. I say, look at the advertising in TV and look at the three letters of the name, of the things they suggest. And see what you see. The names end in mab meaning monoclonal antibody.


ZIERLER: There it is, right.


AMZEL: So that is for sure. PI3K, also appear in one of the TV advertising. One of the drugs targets PI3K. And then probably those two, and...


ZIERLER: So you're defining success in terms of how applicable your research is to a pharmaceutical application?


AMZEL: No, I thought that you were looking for that?




AMZEL: I don't.


ZIERLER: I'm, I'm asking you how you define success.


AMZEL: Yeah, my impression, and it's probably the least cited and very people would even consider that is the final answer. I think I have the correct mechanism for the ATP synthesis published in a paper that's not the mechanism that people are publishing, and I still consider that that's from the biochemistry, biological point of view, that's the most important thing I need. That is the correct mechanism, but you know, people are not using that mechanism, tough luck.


ZIERLER: Are there things that were mysterious to you at the beginning of your career that remain mysterious to you now? After all of the discovery, after all of the advances in technology. What are some of the fundamental mysteries that you're surprised, you might be surprised, remain mysterious to you now? Just as much as they were 40, 50 years ago?


AMZEL: I mean besides the obvious where protein folding, for example, yes, I mean. That's obvious, I think.


ZIERLER: Protein folding, 'cause it's still, it's just not understood?


AMZEL: Correct. Correct.


ZIERLER: Does that suggest to you that it's something that cannot be understood?


AMZEL: No, that's are-- this is one of the things I think that is the opposite, which is when I think there been success now, on predicting, quote-unquote. It's not predicting, because it's wrong. It's wrong some percentage of the times, so that's not a prediction. That's a projection. It's a protein folding, the best people, the best people do is when they use artificial intelligence, they use big data, they use all the things which are just statistical. They provide no information different from the one I know since I was new in this field, about how-- why and how proteins fold.




AMZEL: No information whatsoever.


ZIERLER: And what would be unlocked if we did understand how proteins fold? What would that mean?


AMZEL: No. I don't think life would be any diff-- (laughs) life would be any different. But from my perspective, I would say, "Now I understand how proteins fold."


ZIERLER: But it's more than just you learning something--


AMZEL: Yes, no, no, that mean everybody should know how proteins fold.


ZIERLER: No, but I'm saying, so if you did know how proteins fold, folded, what, what would that mean? What would it mean in terms of clinical, therapy, any of those things?


AMZEL: Any of those things? You can predict; you would be able to predict mutations that will change specificity of proteins. You can predict mutations. You can do that. But it's quite empirical. You could predict modifications to proteins that will make them more efficient or less efficient in ways that you want to intervene clinically or in, in ways... One thing I want to say which I many times thought it wasn't the occasion, I have to say it and I want--


ZIERLER: Please, please.


AMZEL: When I say, "intervene" clinically, I also mean intervene in research. If I can guide somebody to make a compound, that allows them to discover something that they couldn't discover before, I'm happier than I will be in my life.


ZIERLER: Yeah. Why? Why would that make you so happy?


AMZEL: Sorry?


ZIERLER: Why would that make you so happy?


AMZEL: Because in reality, I'm, I'm here for that. I'm not for-- I'm not here to make a medication. I'm here for people to understand how things work.


ZIERLER: Final question.




ZIERLER: What are you excited about in the future? Both within your lifetime and beyond your lifetime? However you want to define the future. What are the things that you feel your field is, is really on the cusp of understanding that are within grasp within, you know, the next generation? What are those things that are exciting to you, and how does that motivate you in terms of your continuing contributions and activity in the field?


AMZEL: Now, that's an interesting question. Well, the first thing that, it doesn't necessarily answer your question, but is, is a sidestep. Which is if people find a platform to be able to use machine learning information and big data information for discovering relation to first principles, that will be outstanding. But this is just a, a sideline. What is one question, interesting. No, maybe that is... Is, is your question about, is there a first principle platform for biology? Yeah.


ZIERLER: That's a legitimate question.


AMZEL: Oh that is, as I said, it's a good question. (laughs)


ZIERLER: And you think that it possibly has an answer?


AMZEL: I hope it has an answer.


ZIERLER: And what would it take to get to that answer? Is it advances in technology? Is it imagination? Is it, is it machine learning? What would it take to get to that answer?


AMZEL: Advances in technology is always necessary, because they, they always provide new. But no, maybe we have all the information necessary. Remember, I mean, the only thing that we need is one more theory in...


ZIERLER: Biology.


AMZEL: In biology, for the moment we have evolution. There is more information that Darwin gathered. But to the other people that were already thinking with the information that was only information. The more information you have, the logical jump becomes a little bit clearer.




AMZEL: But, maybe we have all the information we need. But I don't know.


ZIERLER: That's the problem, you don't even know if you have all the information.


AMZEL: Correct. Correct, correct. Correct.


ZIERLER: Well, Dr. Amzel, this was an absolute pleasure. Thank you so much for spending your time with me.


AMZEL: Well, and I don't know if I have... anything to continue, but you know, the questions were fun, yes.


ZIERLER: Thank you so much.


AMZEL: No, thank you.