Cofactors and Chemsitry

S-Andenosyl Methionine

Chemical structure of S-Andenosyl Methionine 3D representation of S-Andenosyl Methionine

SAM donates a methyl (-CH3) group to some reactions in the synthesis pathways of nucleotides, creatine, epinephrine and phosphatydyl choline. It is also the methyl donor for the modified bases in tRNA and DNA (shown below)
In this reaction The DNA base is methylated. This reaction is important part of metagenetics. Methylation is part of what determines whether or not a gene is translated and transcribed - (expressed). Other factors are also essential in this process as well. Not all of the critical features are understood.