Abstract
It was observed that alliinase was capable to decompose sulfoxide of S-(2-methyl-4-aminopyrimidinyl-(5)-methyl)-cysteine, which is the reaction product of thiamine and cysteine catalyzed with the purified bacterial thiaminase I, and produced pyruvic acid stoichiometrically. A presumed allicin substance was positive to sodium nitroprusside and phosphomolybdic acid reagents, but negative after developing on a paper by means of the paper chromatography. Michaelis constant of alliinase (determined at pH6.4) for S-(2-methyl-4-aminopyrimidinyl-(5)-methyl)-cysteine sulfoxide was Km=9.9×10^<-3>M, while Km was 5×10^<-3> for alliin. From the result it is apparent that the sulfur atom of the cysteine derivatives is not essential to link to an aliphatic group such as allyl, methyl, etc., as mentioned somewhere.
