Candidate: William T. Boswell Program: Master of Science in Biology Date: Friday April 6, 2012 Time: 10:00 a.m. Place: George Mason University, Prince William campus Bull Run Hall, Room 249 Thesis Chair: Dr. Monique van Hoek Title: "Investigating the Molecular Determinants of PHB Biosynthesis in Vibrio Campbellii"A copy of the thesis is on reserve in the Johnson Center Library, Fairfax campus. The thesis will not be read at the meeting, but should be read in advance. All members of the George Mason University community are invited to attend.
Polyhydroxyalkanoates (PHA) or bioplastics are small carbon and energy storage polymers commonly found in the bacterial cytosol. The most-characterized PHAs are the poly-hydroxy-butyrates (PHBs), and the biodegradable properties of PHBs make them attractive alternatives to conventional petroleum based plastics. Bacteria produce PHBs in carbon- rich environments when other nutrients such as nitrogen are limited. PHB biosynthesis in the model organism Escherichia coli is controlled by the AtoS-AtoC two-component system (TCS). The AtoS-AtoC TCS directly regulates expression of the atoDAEB operon that encodes proteins responsible for PHB biosynthesis. Similar to E. coli, studies have demonstrated that certain Vibrio species, specifically Vibrio harveyi, can also produce PHBs. Analysis of the V. campbellii BAA-1116 genome suggests that it too possesses homologs of E. coli atoS, atoC, and atoDAEB.