v5.1.0.3
Glycine data from LIS
Type | Homologous_superfamily |
Description | Pyridoxal phosphate is the active form of vitamin B6 (pyridoxine or pyridoxal). Pyridoxal 5'-phosphate (PLP) is a versatile catalyst, acting as a coenzyme in a multitude of reactions, including decarboxylation, deamination and transamination [, , ]. PLP-dependent enzymes are primarily involved in the biosynthesis of amino acids and amino acid-derived metabolites, but they are also found in the biosynthetic pathways of amino sugars and in the synthesis or catabolism of neurotransmitters; pyridoxal phosphate can also inhibit DNA polymerases and several steroid receptors []. Inadequate levels of pyridoxal phosphate in the brain can cause neurological dysfunction, particularly epilepsy [].PLP enzymes exist in their resting state as a Schiff base, the aldehyde group of PLP forming a linkage with the ε-amino group of an active site lysine residue on the enzyme. The α-amino group of the substrate displaces the lysine ε-amino group, in the process forming a new aldimine with the substrate. This aldimine is the common central intermediate for all PLP-catalysed reactions, enzymatic and non-enzymatic [ ].This entry represents the major region of PLP-dependent transferases. This domain has a three layer α/β/α sandwich topology, with mixed β-sheets of 7 strands. The major region can be found in the following PLP-dependent transferase families:Aspartate aminotransferase (AAT)-like enzymes, such as aromatic aminoacid aminotransferase AroAT, glutamine aminotransferase and kynureninase [ ].Beta-eliminating lyases, such as tyrosine phenol lyase and tryptophanase [ ].Pyridoxal-dependent decarboxylases, such as DOPA decarboxylase and glutamate decarboxylase beta (GadB) [ ].Cystathionine synthase-like enzymes, such as cystalysin, methionine gamma-lyase (MGL), and cysteine desulphurase (IscS) [ ].GABA-aminotransferase-like enzymes, such as ornithine aminotransferase and serine hydroxymethyltransferase [ ].Ornithine decarboxylase major domain [ ]. |
Short Name | PyrdxlP-dep_Trfase |