S-adenosylmethionine [SAM] synthetase-gamma (methionine adenosyltransferase 2 subunit alpha MAT2A)

Function

• catalytic subunit of methionine adenosyltransferase 2
• catalyzes the formation of S-adenosylmethionine from methionine & ATP
• biosynthesis; S-adenosyl-L-methionine from L-methionine: step 1/1, context: activated methyl cycle

ATP + L-methionine + H2O
           <-->
phosphate + diphosphate + S-adenosyl-L-methionine

Cofactor:

• binds 2 divalent ions per subunit. Mg+2 or cobalt
• binds 1 K+ per subunit (putative)

Structure

• heterotetramer composed of 2 catalytic alpha subunits (alpha & alpha') (MAT2A) & 1 copy of beta subunit (MAT2B)
• amino-acid biosynthesis; S-adenosyl-L-methionine
• the alpha' subunit is a post-translationally modified version of MAT2A
• belongs to the AdoMet synthetase family

More general terms

• methionine adenosyl transferase
• enzyme catalytic subunit

Component of

• methionine adenosyltransferase 2 (S-adenosylmethionine synthetase 2)

Database

• Kegg: http://www.genome.jp/dbget-bin/www_bget?hsa:4144
• OMIM: https://mirror.omim.org/entry/601468
• UniProt: http://www.uniprot.org/uniprot/P31153.html