Linked Life Data

1599236

Source:http://linkedlifedata.com/resource/pubmed/id/1599236

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
4
pubmed:dateCreated
1992-7-7
pubmed:abstractText
A two-stage process was evaluated for the fermentation of polymeric feedstocks to ethanol by a single, genetically engineered microorganism. The truncated xylanase gene (xynZ) from the thermophilic bacterium Clostridium thermocellum was fused with the N terminus of lacZ to eliminate secretory signals. This hybrid gene was expressed at high levels in ethanologenic strains of Escherichia coli KO11 and Klebsiella oxytoca M5A1(pLOI555). Large amounts of xylanase (25 to 93 mU/mg of cell protein) accumulated as intracellular products during ethanol production. Cells containing xylanase were harvested at the end of fermentation and added to a xylan solution at 60 degrees C, thereby releasing xylanase for saccharification. After cooling, the hydrolysate was fermented to ethanol with the same organism (30 degrees C), thereby replenishing the supply of xylanase for a subsequent saccharification. Recombinant E. coli metabolized only xylose, while recombinant K. oxytoca M5A1 metabolized xylose, xylobiose, and xylotriose but not xylotetrose. Derivatives of this latter organism produced large amounts of intracellular xylosidase, and the organism is presumed to transport both xylobiose and xylotriose for intracellular hydrolysis. By using recombinant M5A1, approximately 34% of the maximal theoretical yield of ethanol was obtained from xylan by this two-stage process. The yield appeared to be limited by the digestibility of commercial xylan rather than by a lack of sufficient xylanase or by ethanol toxicity. In general form, this two-stage process, which uses a single, genetically engineered microorganism, should be applicable for the production of useful chemicals from a wide range of biomass polymers.
pubmed:commentsCorrections
http://linkedlifedata.com/resource/pubmed/commentcorrection/1599236-16347824, http://linkedlifedata.com/resource/pubmed/commentcorrection/1599236-17247100, http://linkedlifedata.com/resource/pubmed/commentcorrection/1599236-1746941, http://linkedlifedata.com/resource/pubmed/commentcorrection/1599236-17816186, http://linkedlifedata.com/resource/pubmed/commentcorrection/1599236-1905520, http://linkedlifedata.com/resource/pubmed/commentcorrection/1599236-2059047, http://linkedlifedata.com/resource/pubmed/commentcorrection/1599236-2252383, http://linkedlifedata.com/resource/pubmed/commentcorrection/1599236-3034866, http://linkedlifedata.com/resource/pubmed/commentcorrection/1599236-3139631, http://linkedlifedata.com/resource/pubmed/commentcorrection/1599236-3139632, http://linkedlifedata.com/resource/pubmed/commentcorrection/1599236-3513699, http://linkedlifedata.com/resource/pubmed/commentcorrection/1599236-3552873, http://linkedlifedata.com/resource/pubmed/commentcorrection/1599236-7446996, http://linkedlifedata.com/resource/pubmed/commentcorrection/1599236-942051
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Apr
pubmed:issn
0099-2240
pubmed:author
pubmed:issnType
Print
pubmed:volume
58
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1128-33
pubmed:dateRevised
2010-9-10
pubmed:meshHeading
pubmed:year
1992
pubmed:articleTitle
Conversion of xylan to ethanol by ethanologenic strains of Escherichia coli and Klebsiella oxytoca.
pubmed:affiliation
Department of Microbiology and Cell Science, University of Florida, Gainesville 32611.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, Non-P.H.S., Research Support, Non-U.S. Gov't