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Title: The ethanol pathway from Thermoanaerobacterium saccharolyticum improves ethanol production in Clostridium thermocellum

Journal Article · · Metabolic Engineering

Clostridium thermocellum ferments cellulose, is a promising candidate for ethanol production from cellulosic biomass, and has been the focus of studies aimed at improving ethanol yield. Thermoanaerobacterium saccharolyticum ferments hemicellulose, but not cellulose, and has been engineered to produce ethanol at high yield and titer. Recent research has led to the identification of four genes in T. saccharolyticum involved in ethanol production: adhE, nfnA, nfnB and adhA. We introduced these genes into C. thermocellum and observed significant improvements to ethanol yield, titer, and productivity. The four genes alone, however, were insufficient to achieve in C. thermocellum the ethanol yields and titers observed in engineered T. saccharolyticum strains, even when combined with gene deletions targeting hydrogen production. Here, this suggests that other parts of T. saccharolyticum metabolism may also be necessary to reproduce the high ethanol yield and titer phenotype in C. thermocellum.

Research Organization:
Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States); Dartmouth College, Hanover, NH (United States)
Sponsoring Organization:
USDOE Office of Science (SC), Biological and Environmental Research (BER)
Grant/Contract Number:
AC05-00OR22725; AC02-05CH11231
OSTI ID:
1394382
Alternate ID(s):
OSTI ID: 1367525; OSTI ID: 1550373
Journal Information:
Metabolic Engineering, Vol. 42, Issue C; ISSN 1096-7176
Publisher:
ElsevierCopyright Statement
Country of Publication:
United States
Language:
English
Citation Metrics:
Cited by: 41 works
Citation information provided by
Web of Science

References (34)

High Ethanol Titers from Cellulose by Using Metabolically Engineered Thermophilic, Anaerobic Microbes journal September 2011
Increase in Ethanol Yield via Elimination of Lactate Production in an Ethanol-Tolerant Mutant of Clostridium thermocellum journal February 2014
Elimination of hydrogenase active site assembly blocks H2 production and increases ethanol yield in Clostridium thermocellum journal January 2015
Redirecting carbon flux through exogenous pyruvate kinase to achieve high ethanol yields in Clostridium thermocellum journal January 2013
Bacteria engineered for fuel ethanol production: current status journal December 2003
Translation rate is controlled by coupled trade-offs between site accessibility, selective RNA unfolding and sliding at upstream standby sites journal November 2013
Enzymatic Assembly of Overlapping DNA Fragments book May 2011
Dcm methylation is detrimental to plasmid transformation in Clostridium thermocellum journal January 2012
Strain and bioprocess improvement of a thermophilic anaerobe for the production of ethanol from wood journal June 2016
Development and evaluation of methods to infer biosynthesis and substrate consumption in cultures of cellulolytic microorganisms journal April 2013
A defined growth medium with very low background carbon for culturing Clostridium thermocellum journal February 2012
The exometabolome of Clostridium thermocellum reveals overflow metabolism at high cellulose loading journal October 2014
Development of a plasmid-based expression system in Clostridium thermocellum and its use to screen heterologous expression of bifunctional alcohol dehydrogenases (adhEs) journal December 2016
Genetic engineering of Clostridium thermocellum DSM1313 for enhanced ethanol production journal May 2016
Analysis of Relative Gene Expression Data Using Real-Time Quantitative PCR and the 2−ΔΔCT Method journal December 2001
Engineering electron metabolism to increase ethanol production in Clostridium thermocellum journal January 2017
The Bifunctional Alcohol and Aldehyde Dehydrogenase Gene, adhE , Is Necessary for Ethanol Production in Clostridium thermocellum and Thermoanaerobacterium saccharolyticum journal February 2015
Glycolysis without pyruvate kinase in Clostridium thermocellum journal January 2017
Transformation of Clostridium Thermocellum by Electroporation book January 2012
Identifying promoters for gene expression in Clostridium thermocellum journal December 2015
Recent progress in consolidated bioprocessing journal June 2012
Ethanol production by engineered thermophiles journal June 2015
Elimination of metabolic pathways to all traditional fermentation products increases ethanol yields in Clostridium thermocellum journal November 2015
Biological lignocellulose solubilization: comparative evaluation of biocatalysts and enhancement via cotreatment journal January 2016
Elimination of formate production in Clostridium thermocellum journal July 2015
Automated design of synthetic ribosome binding sites to control protein expression journal October 2009
Urease expression in a Thermoanaerobacterium saccharolyticum ethanologen allows high titer ethanol production journal September 2012
Metabolic engineering of a thermophilic bacterium to produce ethanol at high yield journal September 2008
Ferredoxin:NAD + Oxidoreductase of Thermoanaerobacterium saccharolyticum and Its Role in Ethanol Formation journal September 2016
Simultaneous achievement of high ethanol yield and titer in Clostridium thermocellum journal June 2016
Both adhE and a Separate NADPH-Dependent Alcohol Dehydrogenase Gene, adhA , Are Necessary for High Ethanol Production in Thermoanaerobacterium saccharolyticum journal November 2016
Cofactor Specificity of the Bifunctional Alcohol and Aldehyde Dehydrogenase (AdhE) in Wild-Type and Mutant Clostridium thermocellum and Thermoanaerobacterium saccharolyticum journal May 2015
Hydrogen Formation and Its Regulation in Ruminococcus albus: Involvement of an Electron-Bifurcating [FeFe]-Hydrogenase, of a Non-Electron-Bifurcating [FeFe]-Hydrogenase, and of a Putative Hydrogen-Sensing [FeFe]-Hydrogenase journal August 2014
Physiological roles of pyruvate ferredoxin oxidoreductase and pyruvate formate-lyase in Thermoanaerobacterium saccharolyticum JW/SL-YS485 journal September 2015

Cited By (13)

Deletion of the hfsB gene increases ethanol production in Thermoanaerobacterium saccharolyticum and several other thermophilic anaerobic bacteria journal November 2017
Expressing the Thermoanaerobacterium saccharolyticum pforA in engineered Clostridium thermocellum improves ethanol production journal September 2018
Metabolome analysis reveals a role for glyceraldehyde 3-phosphate dehydrogenase in the inhibition of C. thermocellum by ethanol journal November 2017
Metabolic and evolutionary responses of Clostridium thermocellum to genetic interventions aimed at improving ethanol production journal March 2020
Enhanced ethanol formation by Clostridium thermocellum via pyruvate decarboxylase journal October 2017
Metabolic engineering of Clostridium thermocellum for n-butanol production from cellulose journal July 2019
Building a genome engineering toolbox in nonmodel prokaryotic microbes journal May 2018
A mutation in the AdhE alcohol dehydrogenase of Clostridium thermocellum increases tolerance to several primary alcohols, including isobutanol, n-butanol and ethanol journal February 2019
Clostridium thermocellum LL1210 pH homeostasis mechanisms informed by transcriptomics and metabolomics journal April 2018
Expression of adhA from different organisms in Clostridium thermocellum journal November 2017
Engineering Clostridium for improved solvent production: recent progress and perspective journal May 2019
Recent advances of biofuels and biochemicals production from sustainable resources using co-cultivation systems journal June 2019
The redox-sensing protein Rex modulates ethanol production in Thermoanaerobacterium saccharolyticum journal April 2018