has role is deprotonated form of has functional parent independent continuant S-adenosyl-L-methionine L-methioninate sulfonium betaine S-adenosyl-L-methioninate S-Adenosylmethionine A sulfonium betaine that is a conjugate base of <i>S</i>-adenosyl-<small>L</small>-methionine obtained by the deprotonation of the carboxy group. AdoMet [(3S)-3-amino-3-carboxylatopropyl](5'-deoxyadenosin-5'-yl)(methyl)sulfonioacetate [(3S)-3-amino-3-carboxylatopropyl](5'-deoxyadenosin-5'-yl)(methyl)sulfonioacetate SAM human metabolite