| S wave | A negative (downward) deflection of the QRS complex following an R w; successive downward deflections within the same QRS complex are labelled S', S'', etc. (05 Mar 2000) |
|---|---|
| S-(dinitrophenyl)glutathione ATPase | <enzyme> Anionic conjugates of bilirubin and bile acids stimulate the hydrolysis of the above enzyme of human erythrocyte; also found in other tissue Registry number: EC 3.6.1.- Synonym: dnp-sg-atpase (26 Jun 1999) |
| S-A node | <anatomy, cardiology, physiology> The impulse generating (pacemaker) tissue located in the right atrium, under the epicardium at the upper end of the sulcus terminalis. The specialised cardiac muscle fibres generate cardiac impulses that normally acts as the pacemaker of the cardiac conduction system. Normal impulses start in the sinoatrial node and are transmitted to the ventricles, through the atrioventricular node and into the bundle of His. Synonym: nodus sinuatrialis, atrionector, Flack's node, Keith and Flack node, Keith's node, Koch's node, sinoatrial node, sinus node. (20 Jun 2000) |
| S-adenosyl methionine thioether S-methyltransferase | <enzyme> 30,000 da enzyme methylates selenium in dimethylselenide, tellurium in dimethyltelluride, sulfur in dimethylsulfide and other thio ethers. Registry number: EC 2.1.1.- Synonym: dimethyl selenide methyltransferase, thioether methyltransferase (26 Jun 1999) |
| S-adenosyl-l-homocysteine | S-(5'-deoxy-5'-adenosyl)-l-homocysteine;the compound formed by the demethylation of S-adenosyl-l-methionine. (05 Mar 2000) |
| S-adenosyl-l-methionine | S-(5'-deoxy-5'-adenosyl)-l-methionine;condensation product of adenosine and l-methionine involving replacement of the -OPO3H2 of adenylic acid by -S+ (CH3)CH2CH2CH(NH3+)CO 2 of methionine; a sulfonium compound bearing a methyl group that is transferred in transmethylation reactions. See: methionine adenosyltransferase. Synonym: active methionine. Acronym: SAM (05 Mar 2000) |
| S-adenosyl-L-methionine - scoulerine-9-O-methyltransferase | <enzyme> Catalyses the transfer of the s-methyl group of s-adenosyl-l-methionine to the 9-hydroxyl group of scoulerine during the biosynthesis of berberine; from cultured cells of coptis japonica; genbank d29809 Registry number: EC 2.1.1.- Synonym: adenosyl-met-smt, scoulerine 9-o-methyltransferase (26 Jun 1999) |
| S-adenosyl-L-methionine-2-octaprenyl-3-methyl-5-hydroxy-6-methoxy-1,4-benzoquinone-O-methyltransferase | <enzyme> Proposed pathway for final reaction in ubiquinone biosynthesis. Registry number: EC 2.1.1.- Synonym: 2-octaprenyl-3-methyl-5-hydroxy-6-methoxy-1,4-benzoquinone methyltransferase, ubig gene product, ubig protein (26 Jun 1999) |
| S-adenosyl-L-methionine-macrocin O-methyltransferase | <enzyme> Requires mg(ii) and s-adenosyl-l-methionine; specifically converts macrocin to tylosin by o-methylation at 3'''-position of macrocin Registry number: EC 2.1.1.- Synonym: macrocin o-methyltransferase, macrocin o-mt (26 Jun 1999) |
| S-adenosyl-L-methionine-norcoclaurine 6-O-methyltransferase | <enzyme> Catalyses the transfer of the s-methyl group of s-adenosyl-l-methionine to the 6-hydroxy group of norcoclaurine to produce coclaurine toward the synthesis of berberine in coptis japonica Registry number: EC 2.1.1.- Synonym: norcoclaurine 6-o-methyltransferase (26 Jun 1999) |
| s-adenosylhomocysteine | <chemical> 5'-s-(3-amino-3-carboxypropyl)-5'-thioadenosine. Formed from s-adenosylmethionine after transmethylation reactions. Chemical name: L-Homocysteine, S-(5'-deoxyadenosin-5'-yl)- (12 Dec 1998) |
| S-adenosylhomocysteine deaminase | <enzyme> From streptomyces flocculus; deaminating enzyme responsible for the conversion of s-adenosylhomocysteine to s-inosylhomocysteine Registry number: EC 3.5.4.- Synonym: adohcy deaminase (26 Jun 1999) |
| s-adenosylmethionine | <chemical> 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. It is an abundant protein of the retina and pineal gland that elicits experimental autoimmune uveitis, now known to be arrestin. Also a soluble heat stable antigens (195 kD) on the surface of Plasmodium falciparum that are responsible for antigenic heterogeneity. Chemical name: Adenosine, 5'-((3-amino-3-carboxypropyl)methylsulfonio)-5'-deoxy-, inner salt, (3S)- (22 Sep 2002) |
| S-adenosylmethionine - tRNA ribosyltransferase-isomerase | <enzyme> Converts the queuosine precursor, 7-(aminomethyl)-7-deazaguanine (preq1) to epoxyqueuosine (oq) by attachment of an epoxycyclopentanediol moiety Registry number: EC 2.4.2.- Synonym: quea enzyme, quea gene product (26 Jun 1999) |
| S-adenosylmethionine-3,4-dihydroxy-5-polyprenylbenzoate-O-methyltransferase | <enzyme> Involved in ubiquinone biosynthesis Registry number: EC 2.1.1.- Synonym: 3,4-oh-5-ppb-o-me-transferase (26 Jun 1999) |