Monday, May 2, 2011
Grand Ballroom C-D, 2nd fl (Sheraton Seattle)
Thermoanaerobacterium saccharolyticum is a thermophilic anaerobe considered a candidate organism for consolidated bioprocessing (CBP). This organism can degrade xylan and grow on the products of xylan hydrolysis, and has been genetically engineered to produce ethanol at high yield. As such, its xylanase system is of interest for the production of biofuels from lignocellulosic material. The relative importance of several xylanase enzymes in T. saccharolyticum was investigated through deletion analysis, targeting known and putatitive enzymes involved in xylan degradation and utilization. Growth experiments show the importance of beta-xylosidase on the hydrolysis of xylan for T. saccharolyticum as well as an additional endoxylanase beyond the previously characterized xynA and xynB endoxylanases. Differences in xylo-oligomer pools measured during growth on xylan indicate these enzymes work in a synergistic nature. A better understanding of the mechanisms used by T. saccharolyticum may allow for the rational engineering of a more efficient xylan utilization system into other organisms. In addition, xylanase mutants can help understand the role accumulation of xylose and xylo-oligomers play in the inhibition of cellulase activity