Genetic changes that increase 5-hydroxymethyl furfural resistance in ethanol-producing Escherichia coli LY180.
The ability of a biocatalyst to tolerate furan inhibitors present in hemicellulose hydrolysates is important for the production of renewable chemicals. This study shows EMFR9, a furfural-tolerant mutant of ethanologenic E. coli LY180, has also acquired tolerance to 5-hydroxymethyl furfural (5-HMF). The mechanism of action of 5-HMF and furfural appear similar. Furan tolerance results primarily from lower expression of yqhD and dkgA, two furan reductases with a low K(m) for NADPH. Furan tolerance was also increased by adding plasmids encoding a NADPH/NADH transhydrogenase (pntAB). Together, these results support the hypothesis that the NADPH-dependent reduction of furans by YqhD and DkgA inhibits growth by competing with biosynthesis for this limiting cofactor.
Department of Microbiology and Cell Science, University of Florida, Gainesville, FL 32611, USA.
E N
EN
Miller
P C
PC
Turner
L R
LR
Jarboe
L O
LO
Ingram
D000429:Alcohol Oxidoreductases / Q000096:biosynthesis / Q000235:genetics; D000449:Aldehyde Reductase / Q000096:biosynthesis / Q000235:genetics; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D001711:Biotransformation; D024881:Drug Resistance, Bacterial; D004926:Escherichia coli / Q000187:drug effects* / Q000235:genetics / Q000378:metabolism*; D029968:Escherichia coli Proteins / Q000096:biosynthesis / Q000235:genetics; D000431:Ethanol / Q000378:metabolism*; D005662:Furaldehyde / Q000031:analogs & derivatives* / Q000494:pharmacology; D015870:Gene Expression; D009247:NADH, NADPH Oxidoreductases / Q000096:biosynthesis / Q000235:genetics; D010084:Oxidation-Reduction
D000900:Anti-Bacterial Agents; D029968:Escherichia coli Proteins; D000431:Ethanol; C008046:5-hydroxymethylfurfural; D005662:Furaldehyde; D000429:Alcohol Oxidoreductases; C509066:DkgA protein, E coli; D000449:Aldehyde Reductase; C528732:YqhD protein, E coli; D009247:NADH, NADPH Oxidoreductases; C021842:NADH-NAD transhydrogenase