Dehydrogenases

Dehydrogenases are enzymes that catalyze the removal of two hydrogen atoms from a substrate. They catalyze reactions in which oxygen is not a direct electron or hydrogen acceptor. This is a diverse group of enzymes performing this primary function: transferring hydrogen from one substrate to another. Dehydrogenases are specific enzymes that catalyze both reversible and irreversible reactions. Those dehydrogenases whose coenzyme is NAD oxidize substrates containing a [-CH(OH)-] fragment in the molecule. Dehydrogenases with FAD often oxidize substrates with a [-CH₂-CH₂-] fragment in the molecules. Dehydrogenases determine the oxidation of one substrate by another. Respiratory chain complexes, except for cytochrome oxidase, are dehydrogenases that transfer electrons from reduced coenzymes (NADH and FADH₂) to cytochrome oxidase.

Source | Glossary of Most Commonly Used Biomedical Terms and Concepts | Lithuanian University of Health Sciences | Academician Professor Antanas Praškevičius, Professor Laima Ivanovienė