BioChem - DOS

Increased furfural tolerance due to overexpression of NADH-dependent oxidoreductase FucO in Escherichia coli strains engineered for the production of ethanol and lactate

Applied and environmental microbiology

Wang, X.; Miller, E. N.; Yomano, L. P.; Zhang, X.; Shanmugam, K. T.; Ingram, L. O.

<P><B>ABSTRACT</B><P> Furfural is an important fermentation inhibitor in hemicellulose sugar syrups derived from woody biomass. The metabolism of furfural by NADPH-dependent oxidoreductases, such as YqhD (low <I> K m</I> for NADPH), is proposed to inhibit the growth and fermentation of xylose in Escherichia coli by competing with biosynthesis for NADPH. The discovery that the NADH-dependent propanediol oxidoreductase (FucO) can reduce furfural provided a new approach to improve furfural tolerance. Strains that produced ethanol or lactate efficiently as primary products from xylose were developed. These strains included chromosomal mutations in <I>yqhD</I> expression that permitted the fermentation of xylose broths containing up to 10 mM furfural. Expression of <I>fucO</I> from plasmids was shown to increase furfural tolerance by 50% and to permit the fermentation of 15 mM furfural. Product yields with 15 mM furfural were equivalent to those of control strains without added furfural (85% to 90% of the theoretical maximum). These two defined genetic traits can be readily transferred to enteric biocatalysts designed to produce other products. A similar strategy that minimizes the depletion of NADPH pools by native detoxification enzymes may be generally useful for other inhibitory compounds in lignocellulosic sugar streams and with other organisms. </P></P>

2011

American Society for Microbiology

0099-2240

1098-5336

77

15

pp.5132-5140

10.1128/aem.05008-11

http://click.ndsl.kr/servlet/OpenAPIDetailView?keyValue=05787966&target=NART&cn=NART57240823

https://aem.asm.org/content/aem/77/15/5132.full.pdf