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.
Miller
E N
EN
Department of Microbiology and Cell Science, University of Florida, Gainesville, FL 32611, USA.
Turner
P C
PC
Jarboe
L R
LR
Ingram
L O
LO
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