Type: | Family | Name: | Histamine N-methyltransferase-like |
Description: | This group represents histamine N-methyltransferase, which inactivates histamine by N-methylation. It plays an important role in degrading histamine and in regulating the airway response to histamine []. This entry also includes chicken carnosine N-methyltransferase, which may be a paralogue of histamine N-methyltransferase []. Methyltransferases (EC 2.1.1.-) constitute an important class of enzymes present in every life form. They transfer a methyl group most frequently from S-adenosyl L-methionine (SAM or AdoMet) to a nucleophilic acceptor such as oxygen leading to S-adenosyl-L-homocysteine (AdoHcy) and a methylated molecule [, , ]. All these enzymes have in common a conserved region of about 130 amino acid residues that allow them to bind SAM []. The substrates that are methylated by these enzymes cover virtually every kind of biomolecules ranging from small molecules, to lipids, proteins and nucleic acids [, , ]. Methyltransferase are therefore involved in many essential cellular processes including biosynthesis, signal transduction, protein repair, chromatin regulation and gene silencing [, , ]. More than 230 families of methyltransferases have been described so far, of which more than 220 use SAM as the methyl donor. | Short Name: | HHMT-like |