I received my PhD in 1978 from The University of Texas at Austin with Bob Tabita studying the enzyme RuBisCO from Rhodospirillum rubrum. I continued my research on autotrophic prokaryotes during my postdoctoral studies with Ralph Wolfe on the methane-producing Archaea. I joined the Department of Microbiology at the University of Georgia in 1982. My laboratory uses an integrated approach to understand the nature of free-living prokaryotes of environmental importance. I believe that studying the ecology provides insight into the systematics provides insight into the physiology provides insight into the molecular biology and biochemistry. Likewise, the history or evolution provides insight into modern organisms. I have encouraged my students to use these approaches to study the methane-producing archaeon Methanococcus, the marine roseobacteria, and soil bacteria.
Since 2006, I have served as Director of the Editorial Office for Bergeys Manual Trust and worked on the 2nd edition of Bergeys Manual of Systematic Bacteriology, volumes 3-5, including descriptions of the Actinobacteria, Firmicutes, Bacteriodetes, and a number of other taxa. Currently, I am also Treasurer of Bergeys International Society for Microbial Systematics.