title: Enhancement of xylose utilization from corn stover by a recombinant Escherichia coli strain for ethanol production.
abstract: Effects of substrate-selective inoculum prepared by growing on glucose, xylose, arabinose, GXA (glucose, xylose, arabinose, 1:1:1) and corn stover hydrolyzate (dilute acid pretreated and enzymatically hydrolyzed, CSH) on ethanol production from CSH by a mixed sugar utilizing recombinant Escherichia coli (strain FBR5) were investigated. The initial ethanol productivity was faster for the seed grown on xylose followed by GXA, CSH, glucose and arabinose. Arabinose grown seed took the longest time to complete the fermentation. Delayed saccharifying enzyme addition in simultaneous saccharification and fermentation of dilute acid pretreated CS by the recombinant E. coli strain FBR5 allowed the fermentation to finish in a shorter time than adding the enzyme simultaneously with xylose grown inoculum. Use of substrate selective inoculum and fermenting pentose sugars first under glucose limited condition helped to alleviate the catabolite repression of the recombinant bacterium on ethanol production from lignocellulosic hydrolyzate.
authors.affiliation: Bioenergy Research Unit, National Center for Agricultural Utilization Research, Agricultural Research Service, U.S. Department of Agriculture, Peoria, IL 61604, USA(1). Electronic address: Badal.Saha@ars.usda.gov.
authors.forename: Badal C
authors.initials: BC
authors.lastname: Saha
authors.affiliation: Bioenergy Research Unit, National Center for Agricultural Utilization Research, Agricultural Research Service, U.S. Department of Agriculture, Peoria, IL 61604, USA(1).
authors.forename: Nasib
authors.initials: N
authors.lastname: Qureshi
authors.affiliation: Bioenergy Research Unit, National Center for Agricultural Utilization Research, Agricultural Research Service, U.S. Department of Agriculture, Peoria, IL 61604, USA(1).
authors.forename: Gregory J
authors.initials: GJ
authors.lastname: Kennedy
authors.affiliation: Bioenergy Research Unit, National Center for Agricultural Utilization Research, Agricultural Research Service, U.S. Department of Agriculture, Peoria, IL 61604, USA(1).
authors.forename: Michael A
authors.initials: MA
authors.lastname: Cotta
mesh_terms: D002480:Cellulase / Q000737:chemistry; D004926:Escherichia coli / Q000145:classification / Q000502:physiology*; D000431:Ethanol / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism*; D024861:Genetic Enhancement / Q000379:methods; D005947:Glucose / Q000737:chemistry / Q000378:metabolism*; D006868:Hydrolysis; D035261:Plant Components, Aerial / Q000737:chemistry / Q000378:metabolism*; D011995:Recombination, Genetic / Q000502:physiology; D014994:Xylose / Q000737:chemistry / Q000378:metabolism*; D003313:Zea mays / Q000737:chemistry / Q000382:microbiology*; D001617:beta-Glucosidase / Q000737:chemistry
chemical_list: D000431:Ethanol; D014994:Xylose; D001617:beta-Glucosidase; D002480:Cellulase; D005947:Glucose
keywords: Corn stover; Ethanol; Recombinant ethanologenic Escherichia coli; Simultaneous saccharification and fermentation; Substrate selective inoculum