Alkylcysteine sulfoxides

AFFINITY LABELING S-ALKYLCYSTEINE LYASE S-Alkylcysteine sulfoxide lyase,... 

S Alkylcysteine Sulfoxide Lyase (alliinase), the Allium Flavor Enzyme... 

The C-S lyase [alliin alkyl-sulfenate-lyase (EC 4.4.1.4), alliinase, alliin lyase, alkylcysteine sulfoxide lyase, cysteine sulfoxide lyase] is an enzyme responsible for the flavor production Ifom 5 -alk(en)yl-L-... 

The important precursors of onion flavor, the S-alkylcysteine sulfoxides, are formed as follows ... 

Some aspects of the catabolism of cystine in Brassica species have already been discussed in Section V,A. Mazelis et al. (1982) and Hamamoto and Ma-zelis (1986) reported cystine lyase preparations from turnip roots and broccoli buds which were active against cystine and S-alkylcysteine sulfoxides but were inactive toward cystathionine. Hall and Smith (1983) purified two isoenzymes of cystine lyase from cabbage leaves, the more active of which was inactive toward cystathionine. Both isoenzymes supported the production of pyruvate from 5-methylcysteine sulfoxide at rates faster than those obtained with L-cys-tine. However, the values for these substrates were considerably greater than... 

S-Alkylcysteine C-S Lyase (EC 4.4.1.6). The endosperm of seeds of the shrub Albizzia lophanta contains djenkolic acid (HOOCCH(NH2)-CH2SCH2SCH2CH(NH2)C00H) and an enzyme which cleaves it to pyruvate, ammonia, and highly odoriferous substances (CH2(SH)2 ) (48, 49). The enzyme has been purified 200-fold by acid and heat treatment, (NH4)2S04 precipitation, and adsorption on alumina (50). It has a broad specificity and cleaves S-derivatives of L-cysteine, its sulfoxide, and sulfone. L-Cysteine itself is cleaved to pyruvate, HjS, and ammonia. 

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