Dehydrogenasereductases

Dehydrogenasereductases is an umbrella term sometimes used to refer to enzymes that catalyze redox reactions, including both dehydrogenases and reductases. These enzymes participate in a wide range of biological processes by transferring electrons and protons between substrates and cofactors, most commonly nicotinamide adenine dinucleotide in its oxidized or reduced forms (NAD+/NADH or NADP+/NADPH). Depending on the direction of the reaction in a given metabolic context, the same enzyme can function as a dehydrogenase (oxidation, often removing hydrogen) or as a reductase (reduction, adding hydrogen).

Most dehydrogenases and reductases rely on nucleotide cofactors to shuttle hydride ions and to stabilize reaction intermediates. A large and diverse set of families share this chemistry, with common structural motifs such as the Rossmann fold for dinucleotide binding. Many enzymes involved in metabolism exhibit broad substrate scope or high stereospecificity, and the directionality of the reaction is governed by cellular conditions, substrate availability, and cofactor balance.

Notable examples include lactate dehydrogenase, which interconverts lactate and pyruvate with NADH/NAD+, and alcohol dehydrogenase, which catalyzes interconversion of alcohols and aldehydes or ketones. Other families, such as carbonyl reductases and the aldo-keto reductase (AKR) group, primarily act as reductases in detoxification and biosynthesis pathways, often using NADPH. The short-chain dehydrogenase/reductase (SDR) family is a major and well-studied group within this broader category.

In biology and industry, these enzymes are central to energy metabolism, steroid and fatty acid synthesis, xenobiotic detoxification, and the synthesis of chiral intermediates for pharmaceuticals via biocatalysis.