The modified form of the xylose reductase (XR) of Pichia stipitis with decreased affinity toward NADPН(H⁺) was created via site-specific mutagenesis. Recombinant strain of P. stipitis overexpressing the mutated XR characterized by 1,3-fold increase in productivity of xylose alcoholic fermentation was constructed. The rates of alcoholic fermentation of hydrolyzates of wheat bran and sawdust were also improved.

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