ABSTRACT
This Reflections article is focused on the 5 years while I was a graduate student (1964-1969). During this period, I made some of the most significant discoveries of my career. I have written this article primarily for a protein biochemistry audience, my colleagues who shared this exciting time in science, and the many scientists over the last 50 years who have contributed to our knowledge of transcriptional machinery and their regulation. It is also written for today's graduate students, postdocs, and scientists who may not know much about the discoveries and technical advances that are now taken for granted, to show that even with methods primitive by today's standards, we were still able to make foundational advances. I also hope to provide a glimpse into how fortunate I was to be a graduate student over 50 years ago in the golden age of molecular biology.
Subject(s)
DNA-Directed RNA Polymerases , Escherichia coli Proteins , Escherichia coli , Molecular Biology/history , Sigma Factor , DNA-Directed RNA Polymerases/genetics , DNA-Directed RNA Polymerases/history , DNA-Directed RNA Polymerases/metabolism , Escherichia coli/genetics , Escherichia coli/metabolism , Escherichia coli Proteins/genetics , Escherichia coli Proteins/history , Escherichia coli Proteins/metabolism , History, 20th Century , History, 21st Century , Humans , Portraits as Topic , Sigma Factor/genetics , Sigma Factor/history , Sigma Factor/metabolismSubject(s)
Carbamoyl-Phosphate Synthase (Ammonia)/ultrastructure , Carbamoyl-Phosphate Synthase (Glutamine-Hydrolyzing)/ultrastructure , Multienzyme Complexes/ultrastructure , Biochemistry/history , Carbamoyl-Phosphate Synthase (Ammonia)/history , Carbamoyl-Phosphate Synthase (Ammonia)/metabolism , Carbamoyl-Phosphate Synthase (Glutamine-Hydrolyzing)/history , Carbamoyl-Phosphate Synthase (Glutamine-Hydrolyzing)/metabolism , Catalytic Domain , Crystallography/history , Escherichia coli/enzymology , Escherichia coli Proteins/history , Escherichia coli Proteins/metabolism , Escherichia coli Proteins/ultrastructure , History, 20th Century , Multienzyme Complexes/history , Multienzyme Complexes/metabolism , Structure-Activity RelationshipABSTRACT
My career pathway has taken a circuitous route, beginning with a Ph.D. degree in electrical engineering from The Johns Hopkins University, followed by five postdoctoral years in biology at Hopkins and culminating in a faculty position in biological sciences at the University of Southern California. My startup package in 1973 consisted of $2,500, not to be spent all at once, plus an ancient Packard scintillation counter that had a series of rapidly flashing light bulbs to indicate a radioactive readout in counts/minute. My research pathway has been similarly circuitous. The discovery of Escherichia coli DNA polymerase V (pol V) began with an attempt to identify the mutagenic DNA polymerase responsible for copying damaged DNA as part of the well known SOS regulon. Although we succeeded in identifying a DNA polymerase, one that was induced as part of the SOS response, we actually rediscovered DNA polymerase II, albeit in a new role. A decade later, we discovered a new polymerase, pol V, whose activity turned out to be regulated by bound molecules of RecA protein and ATP. This Reflections article describes our research trajectory, includes a review of key features of DNA damage-induced SOS mutagenesis leading us to pol V, and reflects on some of the principal researchers who have made indispensable contributions to our efforts.
