1. Department of Energy, Environmental and Chemical Engineering, Washington University in St. Louis, One Brookings Drive, CB 1180, St. Louis, Missouri 63130, Fermentation Biotechnology Research Unit, United States Department of Agriculture, Agricultural Research Service (ARS), National Center for Agricultural Utilization Research (NCAUR), Peoria, Illinois 61604, and Department of Biological and Environmental Engineering, Cornell University, 214 Riley-Robb Hall, Ithaca, New York 14853