Life in science

My love for science began with a trip at age 12 to Los Angeles’ Griffith Observatory. My father, a professional photographer, helped me construct a small telescope. I first saw Jupiter's moons, and was captivated by their changing positions. That telescope was not much better than Galileo's, but it still was exciting. I later made my own Newtonian mirror, went to astronomy meetings, met Edwin Hubble and spend time with Thomas Cragg at Mount Wilson Observatory, all before age 16.

As an undergraduate at UCLA in 1955 I wanted to major in astronomy, but was told by the faculty that there were no jobs in astronomy and that UCLA did not even have a PhD program. Still, I took courses in astronomy. In one course, from Prof. George Abell, we plotted the 1957 orbit of a new satellite called Sputnik. Little did we know then that in 5 years there would be plenty of jobs in astronomy. Discouraged from astronomy I switched to Biology and then to Bacteriology. I loved optics, microscopes and imaging and was able to get a part-time undergraduate job in the laboratory of Fritiof Sjostrand who had just come from Sweden to UCLA as professor of zoology. There were 2 electron microscopes, and their technology was as exciting to me as big telescopes. I later decided to stay on as a graduate student in bacteriology, and did my first phage experiments with Professor W. R. Romig. He had a soft southern accent, was very modest, and is not as well recognized in the bacteriophage community as he should be. He was among the very first to show that purified DNA extracted from a phage (SPO1) was infectious when used to transform Bacillus subtilis¹ Bob Romig was an excellent teacher and mentor. He spent a great deal of time with each graduate student, gently pointing out missing control experiments and showing us how to design better experimental protocols. The most exciting part of this graduate experience was linking my phage experiments to electron microscopy. By now I was allowed to use the electron microscopes in the Sjostrand lab, and learned to do negative staining of phage. I discovered that by disrupting bacterial DNA replication by UV irradiation, or Mitomycin C treatment that every variety of Bacillus I examined produced either whole phage or phage parts after these treatments.² I concluded in my PhD thesis, rather boldly, that bacterial genomes were all made in part from bacteriophage genes, which was a somewhat novel idea in 1962.

I was incredibly fortunate to be able to work in the Sjostrand lab. One day, Professor Sjostrand told me one of his visitors needed a tennis partner, and that was to be me. The visitor was Hugh Huxley, and after tennis he showed me how to do negative contrast of macromolecules using uranyl acetate. This was a huge improvement in contrast and resolution.

I also learned how to make novel support films containing holes for mounting ultrathin sections of bacteria and to add additional contrast with uranium salts. Professor Sjostrand was interested in ribosomes, and he sent me to NIH to do microscopy of ribosomes bound to mRNA working with Phillip Leder's group in the lab of Marshall Nirenberg. This helped in the early visualization of polyribosomes.³

At UCLA, Bob Romig often took his graduate students across town to Caltech for important seminars where we met Max Delbruck, Bob Edgar, Dick Epstein, Jean Weigle and a seminar visitor from Geneva, Edouard Kellenberger. Two very important events in my life happened about then. Dick Epstein came to UCLA as a visiting professor to teach virology, because Delbruck said he needed to get away from Caltech. One day I found him sleeping on a lab bench with a newspaper over his head. When he awoke I asked if he had a place to stay. He didn’t, and we offered him the couch in our grad student apartment. He stayed for over a year. That was one of the most exciting educational experiences of my life. He and I would discuss experiments, the nature of science, physics, genetics, biology long into the night and the early mornings. Later, at one visit to Caltech, I gave a seminar on my phage EM, hosted by Edgar. After the talk, a bit worried, I asked Bob “who was that person asking question after question?” Bob said “Oh that's Max (Delbruck) You’re lucky; he usually walks out in the middle of seminars."

Dr. Kellenberger later asked if I wanted to do a post doc in Geneva! I Our NIH application was funded and I joined the Geneva group in 1964. I worked with Dick Epstein on gene dosage experiments using Amber mutants of phage T4.⁴ These turned out to be the most precise phage biology experiments I had ever done. I also worked with Kellenberger on EM of many T4 amber mutant lysates where we discovered the petite or isometric head size variant of T4.⁵ At the time I arrived, the prevailing theory of virus assembly based on EM thin sections of T4 infected cells was that phage DNA condensed first and then the capsid later formed around it. The pioneering work of Kellenberger, Antoinette Ryter and, and Janine Sechaud had developed better ways of preserving and visualizing intracellular phage in thin sections of infected cells. I repeated some of this using the newer methods from Sjostrand and Huxley for increasing contrast, and our results showed that every DNA condensate already had a capsid. Edouard was somewhat concerned so we agreed to recover the same embedded cells he had used and to repeat the sectioning using our methods. Again, every condensate in their samples now showed a capsid. Edouard revised his views⁶ and of course later in vitro results confirmed that both T4 and Lambda DNA are packaged into preformed procapsids.

Geneva was a wonderful place for molecular biology. I worked with Uli Laemmli, Michele Fluck, and other great students and postdocs. Visitors included Francois Jacob, Andre Lwoff, James Watson, Aaron Klug and many people from Paris and Cambridge who either walked, hiked or skied in the nearby Alps. Our biophysics lab across the hall included Werner Arber and postdoc Bill Wood and, across the courtyard Alfred Tissieres in biochemistry with John Collier, Bruce Alberts and many others.

I returned to UCLA as an assistant professor in 1966 and began to teach microbiology and EM. Fortunately there was a great interest in learning EM, and with Edouard, Lucien Caro, and many others we gave courses in Geneva, Oak Ridge and UCLA. Dr. Luis Canedo from Mexico joined our lab for several years and helped set up a Latin America EM course in Mexico City in 1970. This was a turbulent time politically; one day we had to hurriedly evacuate our course when the Mexican army invaded the University campus to quell student uprisings.

Our UCLA research focused on size and shape determination in phage T4. We had a delightful sabbatical collaboration in 1971 with Gus Doerman in Basel, hosted by Kellenberger at the Basel Institute for Immunology, on the characterization of giant T4 particles. This eventually led to the proposal that amino acid changes in the major head protein gene 23 were responsible for the head size changes.⁷ We developed an exchange program with the Bach Institute in Moscow and Director Boris Poglazov. Betty Kutter was also there and began her interest in phage therapy. I visited the Bacteriophage Institute in Georgia with Natasha Abuladze, who later joined our lab at UCLA. She, along with students and postdocs showed that Jon King's idea of a “tape measure” or “ruler” protein (in this case T4 gp29) was right, and that it determined the length of the T4 tail,⁸ as was shown for phage lambda by Isao Katsura.

Bacteriophages serve as wonderful subjects for students to do discovery-based research. With support from HHMI Graham Hatfull at Pittsburgh and Erin Sanders at UCLA developed courses that are now used across the country for high school and undergraduate student to isolate and characterize newly discovered pages from soil samples. Bacteriophages are ubiquitous in the biosphere. Given the ability of phages to carry toxin genes and to convert bacteria into pathogens; the challenges of developing effective phage therapy, their value as models of molecular machines and their utility in discovery-based education, I am sure that the study of bacteriophages will continue to remain an essential part of biology.