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No description available.

Naturally occurring microbial communities from high-salt and/or high-temperature environments were collected from sites across the United States and Puerto Rico and screened for their efficacy in the MixAlco biofuel production platform. The MixAlco process, based on the carboxylate platform, is a sustainable and economically viable platform for converting lignocellulosic biomass to biofuels. Using a mixed culture of anaerobic organisms, lignocellulosic biomass is fermented into carboxylic acids, which are neutralized to their corresponding carboxylate salts. These salts can then be converted into a wide variety of chemical products and fuels (alcohols, gasoline, diesel, jet fuel). The central hypothesis is that microbial communities from relatively extreme environments, having evolved to withstand selection pressures similar to the conditions in the carboxylate platform, will exhibit high rates of biomass conversion. A total of 559 soil communities was screened as inocula in established laboratory-scale fermentations. We used pyrotag sequencing of 16S rRNA genes to characterize the bacterial components of the best-performing microbial communities. The best performing communities converted up to 3 times more biomass to acids than a standard marine community inoculum. The community analyses have allowed us to determine the extent to which the same functional types are favored during fermentation, at both laboratory and demonstration plant scales. In all cases, we observed a shift from the more diverse sediment community to post-fermentation communities with relatively low diversity dominated by organisms in the phylum Firmicutes, specifically Bacilli and Clostridia classes. Despite the fact that the inoculum sources were both geographically and ecologically diverse, all of the post-fermentation communities were more similar to each other in community structure than to the corresponding original inoculum community. In addition, studies of the sediments used as inocula revealed that environmental parameters, such as pH and water content, were significantly correlated with bacterial community composition. The wealth of data provided by current sequencing technologies allowed us to question whether communities with high process performances tend to achieve that performance with similar community structures.

Thesis (Ph.D. 1979) from the Department of Biochemistry, University of Adelaide.

Thesis (Ph. D.)--Oregon State University, 2009. / Printout. Includes bibliographical references (leaves 121-128). Also available on the World Wide Web.

Thesis (Ph. D.)--University of Texas at Austin, 2000. / Vita. Includes bibliographical references (leaves 106-113). Available also in a digital version from Dissertation Abstracts.

Thesis (Ph. D.)--University of Texas at Austin, 2009. / Title from PDF title page (University of Texas Digital Repository, viewed on Sept. 16, 2009). Vita. Includes bibliographical references.

Thesis (M.S.)--Oregon State University, 2007. / Printout. Includes bibliographical references. Also available on the World Wide Web.

Theses (M.S.)--Marshall University, 2007. / Title from document title page. Includes abstract. Document formatted into pages: contains viii, 37 pages. Bibliography: p. 36-37.

Thesis (Ph. D.)--Oregon State University, 2008. / Printout. Includes bibliographical references (leaves 75-87). Also available on the World Wide Web.