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Susan Golden was born in Arkansas in 1958. She attended public high school, where she was involved with the marching band and school newspaper. She entered her undergraduate years, at the Mississippi University for Women, intending to become a journalist, but found herself drawn to the sciences and switched her major to biology.

Golden graduated from MUW after only two years, and was then offered an NIH-financed doctoral program in genetics at the University of Missouri. During her graduate program Golden met her husband, James Golden, another student in the NIH program. At the University of Missouri Golden researched the protein makeup of the photosynthetic center in cyanobacteria, work she continued when she moved to the University of Chicago in 1983.

In 1986 Golden accepted a faculty position at Texas A&M to further her investigation into light dependent gene regulation in bacteria. It was at Texas A&M that Golden was first put into contact with Carl Johnson and Takao Kondo (the two other researchers responsible for the discover of the Kai complex) and first became interested in studying circadian rhythms. Dr. Golden was promoted to Distinguished Professor at Texas A&M in 2003, and then moved to UCSD in 2008 where she is currently a Distinguished Professor and the Director of the Center for Circadian Biology.

Early work
Dr. Golden began her graduate career researching the proteins in the photosynthetic complex of the cyanobacteria Synechoccus elongatus. Golden was the first to mutate the psbA gene and place it into cyanobacteria, confirming the gene as a source of herbicide resistance. During the rest of her graduate work and postdoctoral research at University of Chicago, Dr. Golden continued to work on developing genetic manipulation techniques for Synechoccus elongatus, and eventually became interested in how light influenced expression of photosynthetic genes in the organism. To visualize changes in gene expression Golden attached a luciferase gene to the promoters of the cyanobacterial genes of interest. This approach allowed for quantification of gene expression in vivo, a technique that drew the interest of chronobiologist Carl Johnson.

Discovery of Kai Complex
Golden studies the endogenous rhythms of cyanobacteria, the only group of prokaryotes shown to have circadian clocks. She transformed Synechococcus elongatus, one of the better studied models, with a luciferase reporter gene and showed circadian rhythm in bioluminescence. This was used to discover the cyanobacterial clock, based on three proteins, KaiA, KaiB, and KaiC. In collaboration with Carl H. Johnson and Takao Kondo, she demonstrated circadian rhythms in S. elongatus PCC 7942, the only model organism for a prokaryotic circadian clock. Susan Golden is identifying genes in the S. elongatus genome that contribute to circadian rhythm through reverse genetics, creating a mutation in a gene and screening for mutant phenotypes. Transposons are inserted to recombine in the genome, producing a gene knockout.

The Kai protein circadian system
S. elongatus has a circadian clock with an oscillator based only on three proteins, KaiA, KaiB, and KaiC where rhythm is generated based on KaiC phosphorylation and dephosphorylation in vitro. Photosynthesis is used to send light information, leading to clock-controlled outputs affecting transcription. This 24-hour rhythm can be recreated in vitro with the addition of ATP, the simplest known circadian oscillator. In photosynthesizing cyanobacteria, light drives the clock and darkness resets it. In the dark, quinones are oxidized, and KaiA separates from KaiC and binds quinones, resetting the clock.

Metabolic engineering
Research is also done in how cyanobacteria can be used for industrial purposes, and are an attractive model organism due to simplistic genomes and their use of photosynthesis. Cyanobacteria could be used to replace petroleum fuels in the future through generation of biofuels.

Honors and awards

 * National Science Foundation Presidential Young Investigator Award, 1989 to 1995
 * Fellowship in the American Academy of Microbiology, 2000
 * Texas A&M Distinguished Professor, 2003
 * Member of the Faculty of 1000 Biology
 * Member of the National Academy of Sciences

Selected publications