1 Parent Features
| DB identifier | Type | Name |
|---|---|---|
| IPR002129 | Family | Pyridoxal phosphate-dependent decarboxylase |
| Type: | Family | Name: | Tyrosine decarboxylase, bacteria |
| 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 epsilon-amino group of an active site lysine residue on the enzyme. The alpha-amino group of the substrate displaces the lysine epsilon-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 [].A number of pyridoxal-dependent decarboxylases share regions of sequence similarity, particularly in the vicinity of a conserved lysine residue, which provides the attachment site for the pyridoxal-phosphate (PLP) group [, ]. Among these enzymes are aromatic-L-amino-acid decarboxylase (L-dopa decarboxylase or tryptophan decarboxylase), which catalyses the decarboxylation of tryptophan to tryptamine []; tyrosine decarboxylase, which converts tyrosine into tyramine; and histidine decarboxylase, which catalyses the decarboxylation of histidine to histamine []. These enzymes belong to the group II decarboxylases [, ].This entry represents a family of tyrosine decarboxylases found in Enterococcus faecalisand related species. These enzymes often are encoded next to tyrosine/tyramine antiporter, together comprising a system in which tyrosine decarboxylation can protect against exposure to acid conditions []. This clade differs from the archaeal tyrosine decarboxylases associated with methanofuran biosynthesis. | Short Name: | Tyrosine_deCO2ase_bac |
| DB identifier | Type | Name |
|---|---|---|
| IPR002129 | Family | Pyridoxal phosphate-dependent decarboxylase |
