SAMe; a synthetic form of natural metabolite of amino acid which serves great importance being a co-factor for a number of critical biochemical reactions. In recent years, the production of this small active intracellular molecule gained wide interest due to its important role in human health and its expanding application in pharmaceuticals. The popularity of SAMe has soared recently with talk of its ability to ease depression, protect the liver against lesive agents, and also alleviating osteoarthritis. Chemical and enzymatic synthesis of SAMe not being able to satisfactorily produce the desire isomer have shifted researcher focus towards the other means of producing the same; Biochemical method and fermentation being one of the prospect. P.pastoris a eukaryote able to grow extremely high density cell mass under fermentation conditions can be exploited to overproduce desired SAMe isomer.