Can Enzyme Oligomerization control specificity The case study of human SAM synthetase, unravelling its mechanism for potential application in cancer therapy

S-Adenosylmethionine (SAM) acts as a methyl donor in many biochemical events, the key role of this cofactor in biological system is justified by its abundance and essentiality (Loenen et al. Biochem. Soc. Trans. 2006). Among the organic cofactors, SAM is second only to ATP in terms of cellular concentration (Cantoni et al. Annu Rev Biochem 1975). As proof of its essentiality, intracellularly we found more than 200 methyltransferases which use SAM as a methyl donor and if cells are depleted of SAM, they starve (Parungao et al. Microbiology 2017).Biosynthesis of SAM requires the enzyme methionine adenosyltransferase (MAT) and as starting material ATP and Methionine.