Write on genetic organization & types of mutations observed in T4 genome.
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appeared over 40 years ago in the 1963 Cold Spring Harbor Symposium for Quantitative Biology. The article (Epstein et al.1963) described the phenotypes of 130 conditional-lethal mutants of T4, 69 amber mutants, and 61 temperature-sensitive (ts) lethal mutants and presented a genetic map of these mutations. The mutations were located in 47 different genes, 35 of which appeared to be involved in morphogenesis of the phage particles. When these morphogenesis mutants were grown under restrictive conditions, most of the infective processes appeared to continue normally; there was nuclear breakdown followed by rapid DNA synthesis and cell lysis, but no viable phage were released. Only phage components were produced: heads, or tails, or heads and tails, or particles lacking tail fibers. The locations of these genes are not random on the linkage map. Genes with similar phenotypes are clustered. Mutants defective in each of the other 12 genes showed aberrations in DNA synthesis. They also showed gross defects in cell lysis and phage component production as well. These genes also showed clustering in the genome. We argued that a significant fraction of the essential genes of T4 had been identified.
When I received the invitation to write this Perspectives article, I had almost nothing at hand except my memories. I could not find any of my reprints, and my science files had long since disappeared. I retired in 1990, and for the last 14 years I have engaged almost entirely in nonscientific matters. I recall with some embarrassment that 20 or so years ago the Genetics Society of America asked that I give my papers to the University Library for safekeeping. I then looked at my old notebooks from the 1950s and 1960s—loose-leaf binders with the pages falling out, many undated, just lists of numbers. They were total gibberish to me. I hid them away then and they eventually disappeared. To write this retrospective, I contacted Bill Dove, one of the Perspectives editors, and he sent me a copy of the Cold Spring Harbor article. I was relieved to find that I could still understand the material. My friend and colleague for 50 years, Frank Stahl, also came to my aid and sent me copies of my grant reports for 1961–1963. He also sent me our correspondence from the 1950s and 1960s.
It has been claimed that one of the tasks for the elderly is to create meaning out of what they have done with their lives. I can certainly see that urge now in me, and so I have approached the preparation of this article with considerable interest. I have sifted through the few documents made available to me, and I have dug into my memories and the memories of those who collaborated with me in this work.
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