IUBMB Enzyme Nomenclature


Accepted name: D-xylose reductase (NADPH)

Reaction: xylitol + NADP+ = D-xylose + NADPH + H+

Other name(s): XYL1 (gene name, ambiguous); xyl1 (gene name, ambiguous); xyrA (gene name); xyrB (gene name)

Systematic name: xylitol:NADP+ oxidoreductase

Comments: Xylose reductases catalyse the reduction of xylose to xylitol, the initial reaction in the fungal D-xylose degradation pathway. Most of the enzymes exhibit a strict requirement for NADPH (e.g. the enzymes from Saccharomyces cerevisiae, Aspergillus niger, Trichoderma reesei, Candida tropicalis, Saitozyma flava, and Candida intermedia). Some D-xylose reductases have dual coenzyme specificity, though they still prefer NADPH to NADH (cf. EC, D-xylose reductase [NAD(P)H]). Very rarely the enzyme prefers NADH (cf. EC, D-xylose reductase (NADH)).

Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc, CAS registry number:


1. Bolen, P.L. and Detroy, R.W. Induction of NADPH-linked D-xylose reductase and NAD-linked xylitol dehydrogenase activities in Pachysolen tannophilus by D-xylose, L-arabinose, or D-galactose. Biotechnol. Bioeng. 27 (1985) 302-307. [PMID: 18553673]

2. Suzuki, T., Yokoyama, S., Kinoshita, Y., Yamada, H., Hatsu, M., Takamizawa, K. and Kawai, K. Expression of xyrA gene encoding for D-xylose reductase of Candida tropicalis and production of xylitol in Escherichia coli. J. Biosci. Bioeng. 87 (1999) 280-284. [PMID: 16232468]

3. Nidetzky, B., Mayr, P., Hadwiger, P. and Stutz, A.E. Binding energy and specificity in the catalytic mechanism of yeast aldose reductases. Biochem. J. 344 Pt 1 (1999) 101-107. [PMID: 10548539]

4. Mayr, P., Bruggler, K., Kulbe, K.D. and Nidetzky, B. D-Xylose metabolism by Candida intermedia: isolation and characterisation of two forms of aldose reductase with different coenzyme specificities. J. Chromatogr. B Biomed. Sci. Appl. 737 (2000) 195-202. [PMID: 10681056]

5. Sene, L., Felipe, M.G., Silva, S.S. and Vitolo, M. Preliminary kinetic characterization of xylose reductase and xylitol dehydrogenase extracted from Candida guilliermondii FTI 20037 cultivated in sugarcane bagasse hydrolysate for xylitol production. Appl. Biochem. Biotechnol. 91-93 (2001) 671-680. [PMID: 11963895]

6. Jeong, E.Y., Sopher, C., Kim, I.S. and Lee, H. Mutational study of the role of tyrosine-49 in the Saccharomyces cerevisiae xylose reductase. Yeast 18 (2001) 1081-1089. [PMID: 11481678]

7. Chroumpi, T., Peng, M., Aguilar-Pontes, M.V., Muller, A., Wang, M., Yan, J., Lipzen, A., Ng, V., Grigoriev, I.V., Makela, M.R. and de Vries, R.P. Revisiting a ‘simple’ fungal metabolic pathway reveals redundancy, complexity and diversity. Microb. Biotechnol. 14 (2021) 2525-2537. [PMID: 33666344]

8. Terebieniec, A., Chroumpi, T., Dilokpimol, A., Aguilar-Pontes, M.V., Makela, M.R. and de Vries, R.P. Characterization of D-xylose reductase, XyrB, from Aspergillus niger. Biotechnol Rep (Amst) 30 (2021) e00610. [PMID: 33842213]

[EC created 2022]

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