Protein Domain : C-20 methyltransferase CrtF-related IPR014088

Type	Family
Description	Members of this protein family include bacteriochlorophyllide d C-20 (also known as methyltransferaseS-adenosylmethionine-dependent C-20 methyltransferase or BchU), part of the pathway of bacteriochlorophyll c production in photosynthetic green sulphur bacteria. The position modified by this enzyme represents the difference between bacteriochlorophylls c and d; strains lacking this protein can only produce bacteriochlorophyll d.Methyltransferases (EC [intenz: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	C20_MeTrfase_CrtF