Integrated Genome-Based Studies of Shewanella Echophysiology.

摘要

Shewanella oneidensis MR-1 is a motile, facultative (gamma)-Proteobacterium with remarkable respiratory versatility; it can utilize a range of organic and inorganic compounds as terminal electronacceptors for anaerobic metabolism. The ability to effectively reduce nitrate, S0, polyvalent metals andradionuclides has established MR-1 as an important model dissimilatory metal-reducing microorganism for genome-based investigations of biogeochemical transformation of metals and radionuclides that are of concern to the U.S. Department of Energy (DOE) sites nationwide. Metal-reducing bacteria such as Shewanella also have a highly developed capacity for extracellular transfer of respiratory electrons to solid phase Fe and Mn oxides as well as directly to anode surfaces in microbial fuel cells. More broadly, Shewanellae are recognized free-living microorganisms and members of microbial communities involved in the decomposition of organic matter and the cycling of elements in aquatic and sedimentary systems. To function and compete in environments that are subject to spatial and temporal environmental change, Shewanella must be able to sense and respond to such changes and therefore require relatively robust sensing and regulation systems. The overall goal of this project is to apply the tools of genomics, leveraging the availability of genome sequence for 18 additional strains of Shewanella, to better understand the ecophysiology and speciation of respiratory-versatile members of this important genus.