The expression of a Pichia stipitis xylose reductase mutant with higher K-M for NADPH increases ethanol production from xylose in recombinant Saccharomyces cerevisiae
Xylose fermentation by Saccharomyces cerevisiae requires the introduction of a xylose pathway, either similar to that found in the natural xylose-utilizing yeasts Pichia stipitis and Candida shehatae or similar to the bacterial pathway. The use of NAD(P)H-dependent XR and NAD(+)-dependent XDH from P. stipitis creates a cofactor imbalance resulting in xylitol formation. The effect of replacing the