Hydroksylazy

Hydroksylazy, commonly referred to in English as hydroxylases, are enzymes that catalyze the introduction of hydroxyl groups into organic substrates. They are a subset of oxidoreductases (EC class 1) and play a key role in the metabolism of xenobiotics, natural products, and cellular signaling molecules.

Hydroxylation reactions are typically driven by molecular oxygen. Hydroxylases are broadly divided into monooxygenases, which insert one atom of O2 into the substrate while reducing the other to water, and dioxygenases, which incorporate both oxygen atoms into the substrate. Different families use different cofactors: heme-containing cytochrome P450 monooxygenases; flavin-dependent monooxygenases with FAD or FMN; and non-heme Fe2+/2-oxoglutarate-dependent dioxygenases that require Fe2+ and 2-oxoglutarate as co-substrates.

Prominent examples include cytochrome P450 enzymes involved in drug metabolism and synthesis of steroid hormones; prolyl and lysyl hydroxylases that modify collagen; and plant hydroxylases that participate in hormone biosynthesis such as gibberellins. Microbial hydroxylases participate in degradation of aromatic compounds and other organic pollutants.

Due to their role in metabolism and biosynthesis, hydroksylazy have significant Biomedical and biotechnological relevance, including drug design, bioremediation, and production of hydroxylated natural products. The term is sometimes used interchangeably with hydroxylases, though specific subfamilies differ in mechanism and cofactors.