Buchanan: I’d now like to turn to the early isotope studies you carried out #AMN-107 ic50 randurls[1|1|,|CHEM1|]# in Berkeley. We’ll start with carbon–11, the radioactive form of carbon that Sam Ruben and Martin Kamen used in their early photosynthesis experiments.
Carbon-11 has a half-life of only 20 min, a short time to do an experiment. What were Ruben and Kamen able to accomplish in their carbon-11 experiments in such a short time? Benson: Oh, Sam Ruben published about 30 papers, and in collaboration with all kinds of microbiologists, studied different–different reactions. But they made no progress with respect to the absorption and conversion of carbon dioxide to carbohydrates. Buchanan: In photosynthesis. Benson: Yeah. Buchanan: So his contributions were mainly with bacteria. Benson: Yeah. With many people, in different laboratories. Buchanan: Did he work with Barker? Benson: Yes. Buchanan: And Hassid? Benson: Yeah. Buchanan: —on the campus. So these were early— Benson: Hassid was a good friend of mine. Early photosynthesis experiments Buchanan: So these were early contributions. During this period, Ruben and Kamen discovered carbon-14, Histone Acetyltransferase inhibitor an isotope with
a half-life of more than 5,000 years. Ernest Lawrence, Director of the Radiation Laboratory, saw the great potential of carbon-14, and asked Calvin to continue the work of Ruben and Kamen and apply the isotope in studies of photosynthesis. You joined his research group in 1946. Calvin recognized your experience with carbon-14, but did he appreciate your expertise in carbohydrate chemistry that you acquired at Cal Tech? Benson: No. He didn’t know very much about carbohydrate chemistry. Buchanan: Let’s now discuss the photosynthesis experiments with Carbon-14 O2 that you carried out in Calvin’s laboratory. By the way, Andy, you may be the only living person who has worked with the four carbon isotopes, C-11, C-12, C-13, and C-14. Did this broad experience oxyclozanide help you in your photosynthesis work at Berkeley? Benson:
No, I didn’t worry about that until years later, (laughs) when I wrote an article about it. But that just doesn’t—no great invention or anything. Buchanan: It probably didn’t occur to you (laughs) until sometime later, actually. Benson: Yeah. Buchanan: Can you describe how the C14O2 photosynthesis experiments were carried out, starting with the type of cells that were used? Benson: Well, one of the members of the group was an—was an expert at culturing algae, so Vicky Lynch took care of that side of the problem. Easy to measure the volume of algae. It would be difficult with leaves of plants and things like that, but with algae you spin them down in a centrifuge and measure their—their dimensions and you know how much you got. And at first, I was extracting the radioactive products with toluene and—and ethyl alcohol, which was pretty stupid—until Al Bassham started using methyl alcohol. Because this was perfect.