S-Adenosylhomocysteine Hydrolase as a Pharmacological Target for the Inhibition of Transmethylation
S-Adenosylhomocysteine (AdoHcy) hydrolase catalyzes the reversible cleavage of AdoHcy to adenosine (Ado) and L-homocysteine (Hcy) (Fig. 1). Although the equilibrium of the reaction is very much in the direction of synthesis, with a Keq of about 10−6 M (1), physiologically the reaction proceeds in the hydrolytic direction because Ado and Hcy are efficiently removed by further metabolism. Ado can either be deaminated to inosine by Ado deaminase or be phosphorylated by Ado kinase to AMP. The Hcy produced is either remethylated to methionine by N5-methyltrahydrofolate-Hcy methyltransferase, or converted to cystathionine after condensation with serine by β-cystathionine synthase.
KeywordsThymidine Kinase Pharmacological Target Lupin Seed Beef Liver Keto Butyrate
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