EFFECTS OF ENGINEERING USING BACTERIAL HEMOGLOBIN ON THE ABILITY OF ETHANOLOGENIC E. COLI TO FERMENT LIGNOCELLULOSIC HYRDOLYSATE TO ETHANOL Kunkel, Stephanie E. coli strain FBR5, which has been engineered to direct fermentation of sugars to ethanol has been further engineered in our laboratory using three different constructs, to contain and express the Vitreoscilla hemoglobin gene (vgb). The resulting strain (TS3) expresses VHb at a moderate level under microaerobic conditions in shake flasks and produces more ethanol than the parental strain (FBR5) with glucose, xylose, or corn stover hydrolysate as the carbon source. In the work reported here, this research was extended, focusing particularly on fermentation of lignocellulosic hydrolysate. The increased ability of the VHb-bearing strain to produce ethanol from pure glucose or xylose was confirmed. A VHb-correlated increase in ethanol production was also noted for lignocellulosic hydrolysate produced in our laboratory, but not for ligncellulosic hydrolysate prepared by the National Laboratory for Renewable Energy (NREL). Experiments were performed at several hydrolysate levels for both prepartories, in an attempt to determine the cause of the difference. One possibility is differences in levels of toxic hydrolysis byproducts in the two preparations as well as increased sensitivity to these toxins due to VHb expression. M.S. in Biology, May 2011 Stark, Benjamin C. 2011-05-03 2011-05 Thesis application/pdf islandora:7036 http://hdl.handle.net/10560/2523 BIOL / Biology Illinois Institute of Technology en In Copyright http://rightsstatements.org/page/InC/1.0/ Restricted Access