Biomaterial Database

S-adenosylmethionine-dependent enzyme activation. 1988

J W Kozarich

Department of Chemistry and Biochemistry, University of Maryland, College Park 20742.

S-Adenosylmethionine (SAM)-dependent activations of pyruvate formate-lyase, lysine 2,3-aminomutase and cobalamin-dependent methionine synthase are discussed. In each case, cleavage of SAM is accompanied by the formation of a catalytically active enzyme. The chemistry of activation of these three enzymes falls into three distinct classes: generation of an essential enzyme radical (pyruvate formate-lyase), formation of a catalytically active 5'-deoxyadenosyl radical (lysine 2,3-aminomutase) and reductive methylation to form a required methylcobalamin complex (methionine synthase).

UI	MeSH Term	Description	Entries
D008780	Methyltransferases	A subclass of enzymes of the transferase class that catalyze the transfer of a methyl group from one compound to another. (Dorland, 28th ed) EC 2.1.1.	Methyltransferase
D004789	Enzyme Activation	Conversion of an inactive form of an enzyme to one possessing metabolic activity. It includes 1, activation by ions (activators); 2, activation by cofactors (coenzymes); and 3, conversion of an enzyme precursor (proenzyme or zymogen) to an active enzyme.	Activation, Enzyme,Activations, Enzyme,Enzyme Activations
D000123	Acetyltransferases	Enzymes catalyzing the transfer of an acetyl group, usually from acetyl coenzyme A, to another compound. EC 2.3.1.	Acetyltransferase
D000591	Amino Acid Isomerases	Enzymes that catalyze either the racemization or epimerization of chiral centers within amino acids or derivatives. EC 5.1.1.	Amino Acid Racemase,Amino Acid Racemases,Acid Isomerases, Amino,Acid Racemase, Amino,Acid Racemases, Amino,Isomerases, Amino Acid,Racemase, Amino Acid,Racemases, Amino Acid
D012436	S-Adenosylmethionine	Physiologic methyl radical donor involved in enzymatic transmethylation reactions and present in all living organisms. It possesses anti-inflammatory activity and has been used in treatment of chronic liver disease. (From Merck, 11th ed)	AdoMet,Ademetionine,FO-1561,Gumbaral,S Amet,S-Adenosyl-L-Methionine,S-Adenosylmethionine Sulfate Tosylate,SAM-e,Samyr,FO 1561,FO1561,S Adenosyl L Methionine,S Adenosylmethionine,S Adenosylmethionine Sulfate Tosylate
D013766	5-Methyltetrahydrofolate-Homocysteine S-Methyltransferase	An enzyme that catalyzes the formation of methionine by transfer of a methyl group from 5-methyltetrahydrofolate to homocysteine. It requires a cobamide coenzyme. The enzyme can act on mono- or triglutamate derivatives. EC 2.1.1.13.	Methionine Synthetase,Methyltetrahydrofolate Homocysteine Methyltransferase,Tetrahydropteroylglutamate Methyltransferase,Methionine Synthase,Vitamin B12-Dependent Methionine Synthase,Vitamin B12-Independent Methionine Synthase,Homocysteine Methyltransferase, Methyltetrahydrofolate,Methyltransferase, Methyltetrahydrofolate Homocysteine,Methyltransferase, Tetrahydropteroylglutamate,S-Methyltransferase, 5-Methyltetrahydrofolate-Homocysteine,Synthase, Methionine,Synthetase, Methionine
D019751	Intramolecular Transferases	Enzymes of the isomerase class that catalyze the transfer of acyl-, phospho-, amino- or other groups from one position within a molecule to another. EC 5.4.	Mutases,Transferases, Intramolecular