Recorded: 20 Aug 2006
AR: I was a postdoctoral fellow with Linus Pauling from 1949 to 1954. I worked on many different problems, but began to be interested in the nucleic acids towards the end of that period. Linus at that point had a flash of insight, erroneous it turned out, suggesting that DNA was a triple helix. He formulated that, published it quickly, and I think rapidly realized it was incorrect. At that point he asked me to try to get some experimental data. And so I started drawing fibers of DNA using... What you do when drawing fibers, is you take some dry material, its white, fibrous, dissolve it in a small droplet of water, attach a thin glass rod to the objective lens of a microscope, and screw it down so that it just touches the droplet. Then you slowly withrew it, withdraw. And as you withdraw it, you are left with first a very viscous glob, and eventually it dries down, and becomes a fiber. DNA, in DNA the molecules were fairly long. So after I started in December of 1952, and by February I was getting pretty good orientation. And ah, …but at one point in February Linus told me that two Englishmen had, he learned from a letter from his son, Peter, in Cambridge, that two Englishmen had come up with a different structure of DNA. One with two strands and the bases in the middle. I remember going home that night wondering about what that molecule could look like. I went into the lab, I couldn’t sleep. So I went back to the lab where there was a model room with molecular models. And I started building it, and I realized there was only one way you could make a repeating unit with two bases which, in which they looked rather similar . Namely the A-T and G-C pairs. And so I built a model, and it was right handed and ah, the ah, when the paper came out shortly, I was pleased to see that’s what it looked like. Ah.. at that point well, at that point there was a lot of activity at Caltech…because
MP: Hold on a second.
AR: Linus had organized a conference on protein structure in September. And actually when uh…during that summer I remember… one of the problems that arose from the DNA model was how would you get the strands apart. Max Delbrück in fact felt so strongly about that, he felt they could not come apart. And, I wondered at that point if perhaps, it could also go left handed, and it could be partly right handed, partly left handed. So I was working in the model room trying to make a left handed double helix, again maintaining the kind of base pairing that was there. I remember at one point Linus poked his head in the door and said, “Alex, work on that problem hard. I like most important discoveries to be made in Pasadena.” Ha, ha! It’s rather typical of Linus. What I convinced myself of was that you could not build it left handed. And ah, to my surprise some twenty-five years later, I found it was possible but in a totally different form. The ah, …at the meeting, I uh, …both Jim and Francis were there.
Alexander Rich (b. 1924), biologist and biophysicist, is the William Thompson Sedgwick Professor of Biophysics and Biochemistry, at the Massachusetts Institute of Technology, Department of Biology. Rich first joined the MIT faculty in 1958. Subsequent to serving in the U.S. Navy from 1943-1946, Rich earned his undergraduate degree (A.B., magna cum laude, 1947) and medical degree (M.D., cum laude, 1949) from Harvard University. While doing his postdoctoral work at Caltech under Linus Pauling, Rich met Jim Watson and they began their collaboration on the structure of RNA. From 1969-1980 he was an investigator in NASA's Viking Mission to Mars, the project which designed experiments to determine if there is life on Mars.
Alex Rich's most well-known scientific discoveries are left-handed DNA, or Z-DNA, and the three-dimensional structure of transfer RNA. He has been elected to the the National Academy of Sciences (1970), the American Academy of Arts and Sciences, the Institute of Medicine, the French Academy of Sciences, the Russian Academy of Sciences, and the Pontifical Academy of Sciences (the Vatican.) Among other awards and honorary degrees he has received are the Medal of Science granted by President Clinton in 1995, the Rosentiel Award in Basic Biomedical Research, and the Presidential Award of the New York Academy of Sciences.
Since the 1980s Alex Rich has been actively involved in number of companies in the pharmaceutical and biotechnology industries. He co-founded the pharmaceutical company Alkermes Inc. in 1987 and currently serves as a director. He is also Co-Chairman of the Board of Directors of Repligen Corporation, Inc., a biopharmaceutical company, a member of the Scientific Advisory Board of Roseta Genomics, and a member of the Board of Directors for Profectus Biosciences, Inc.