Rhea - reaction knowledgebase

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Enzymes

UniProtKB ^help_outline	1 proteins
GO Molecular Function ^help_outline	GO:0032018 2-methylbutanal reductase (NADPH) activity

Reaction participants Show >> << Hide

Name ^help_outline 2-methylbutan-1-ol Identifier CHEBI:48945 (CAS: 137-32-6) ^help_outline Charge 0 Formula C5H12O InChIKey^help_outline QPRQEDXDYOZYLA-UHFFFAOYSA-N SMILES^help_outline CCC(C)CO 2D coordinates Mol file for the small molecule Search links Involved in 4 reaction(s) Find molecules that contain or resemble this structure Find proteins in UniProtKB for this molecule
Name ^help_outline NADP⁺ Identifier CHEBI:58349 Charge -3 Formula C21H25N7O17P3 InChIKey^help_outline XJLXINKUBYWONI-NNYOXOHSSA-K SMILES^help_outline NC(=O)c1ccc[n+](c1)[C@@H]1O[C@H](COP([O-])(=O)OP([O-])(=O)OC[C@H]2O[C@H]([C@H](OP([O-])([O-])=O)[C@@H]2O)n2cnc3c(N)ncnc23)[C@@H](O)[C@H]1O 2D coordinates Mol file for the small molecule Search links Involved in 1,372 reaction(s) Find molecules that contain or resemble this structure Find proteins in UniProtKB for this molecule
Name ^help_outline 2-methylbutanal Identifier CHEBI:16182 (CAS: 96-17-3) ^help_outline Charge 0 Formula C5H10O InChIKey^help_outline BYGQBDHUGHBGMD-UHFFFAOYSA-N SMILES^help_outline [H]C(=O)C(C)CC 2D coordinates Mol file for the small molecule Search links Involved in 4 reaction(s) Find molecules that contain or resemble this structure Find proteins in UniProtKB for this molecule
Name ^help_outline NADPH Identifier CHEBI:57783 (Beilstein: 10411862) ^help_outline Charge -4 Formula C21H26N7O17P3 InChIKey^help_outline ACFIXJIJDZMPPO-NNYOXOHSSA-J SMILES^help_outline NC(=O)C1=CN(C=CC1)[C@@H]1O[C@H](COP([O-])(=O)OP([O-])(=O)OC[C@H]2O[C@H]([C@H](OP([O-])([O-])=O)[C@@H]2O)n2cnc3c(N)ncnc23)[C@@H](O)[C@H]1O 2D coordinates Mol file for the small molecule Search links Involved in 1,365 reaction(s) Find molecules that contain or resemble this structure Find proteins in UniProtKB for this molecule
Name ^help_outline H⁺ Identifier CHEBI:15378 Charge 1 Formula H InChIKey^help_outline GPRLSGONYQIRFK-UHFFFAOYSA-N SMILES^help_outline [H+] 2D coordinates Mol file for the small molecule Search links Involved in 10,232 reaction(s) Find molecules that contain or resemble this structure Find proteins in UniProtKB for this molecule

Cross-references

	RHEA:84375	RHEA:84376	RHEA:84377	RHEA:84378
Reaction direction	undefined	left-to-right	right-to-left	bidirectional
UniProtKB ^help_outline	1 proteins		1 proteins
Gene Ontology ^help_outline	GO:0032018

Related reactions ^help_outline

More general form(s) of this reaction

RHEA:15937
a primary alcohol + NADP⁺ = an aldehyde + NADPH + H⁺

Publications

Characterization of Ypr1p from Saccharomyces cerevisiae as a 2-methylbutyraldehyde reductase.

Ford G., Ellis E.M.

The metabolism of aldehydes and ketones in yeast is important for biosynthetic, catabolic and detoxication processes. Aldo-keto reductases are a family of enzymes that are able to reduce aldehydes and ketones. The roles of individual aldo-keto reductases in yeast has been difficult to determine be ... >> More

The metabolism of aldehydes and ketones in yeast is important for biosynthetic, catabolic and detoxication processes. Aldo-keto reductases are a family of enzymes that are able to reduce aldehydes and ketones. The roles of individual aldo-keto reductases in yeast has been difficult to determine because of overlapping substrate specificities of these enzymes. In this study, we have cloned, expressed and characterized the aldo-keto reductase Ypr1p from the yeast Saccharomyces cerevisiae and we describe its substrate specificity. The enzyme displays high specific activity towards 2-methylbutyraldehyde, as well as other aldehydes such as hexanal. It exhibits extremely low activity as a glycerol dehydrogenase. The enzyme functions over a wide pH range and uses NADPH as co-factor. In comparison to other mammalian and yeast aldo-keto reductases, Ypr1p has relatively high affinity for D,L-glyceraldehyde (1.08 mM) and hexanal (0.39 mM), but relatively low affinity for 4-nitrobenzaldehyde (1.07 mM). It displays higher specific activity for 2-methylbutyraldehyde than does yeast alcohol dehydrogenase and has a K(m) for 2-methyl butyraldehyde of 1.09 mM. The enzyme is expressed during growth on glucose, but its levels are rapidly induced by osmotic and oxidative stress. Yeast in which the YPR1 gene has been deleted possess 50% lower 2-methylbutyraldehyde reductase activity than the wild-type strain. This suggests that the enzyme may contribute to 2-methyl butyraldehyde reduction in vivo. It may therefore play a role in isoleucine catabolism and fusel alcohol formation and may influence flavour formation by strains of brewing yeast. << Less

Yeast 19:1087-1096(2002) [PubMed] [EuropePMC]

This publication is cited by 1 other entry.