Objectives

• Study the overall biological CO shift pathway at the physiological, biochemical, and genetic levels. • Improve the rates and durability of H2 production from CO by determining how CO regulates the overall water-gas shift (WGS) pathway by serving as an inducer, a substrate, and an inhibitor. • Elucidate the genetic system of the CO shift reaction to (1) identify the various components involved and (2) allow manipulation of gene expression. • Develop bioreactors that will promote an economic biological WGS reaction. • Design, construct, and operate a bioreactor capable of operating at elevated system pressures. • Measure the specific CO shift kinetics of the photosynthetic bacterium Rubrivivax (Rx.) gelatinosus CBS. Approach • Characterize the physiological and biochemical mechanisms in the CO shift reaction by which Rx. gelatinosus CBS produces H2 from CO. • Clone and characterize genes involved in the Rx. gelatinosus CBS CO shift pathway. • Build on the understanding of the CO shift pathway, optimize the WGS process for maximum H2 production