Cysteine conjugate beta-lyase.
Cysteine conjugate beta-lyase from rat liver, an enzyme participating in a shunt from mercapturic acid synthesis, has been purified and found to be active with a number of compounds that bear nonpolar leaving groups on the beta-carbon of an amino acid substrate. Pyridoxal phosphate is considered to be a participant in the reaction. In addition to aromatic thioethers of cysteine, the enzyme is also active with two aliphatic amino acid derivatives, S-1,2-dichlorovinyl-L-cysteine and beta-chloroalanine. Evidence is presented that catalysis results in "suicide" inhibition with a partition ratio of about 600 for each of the substrates.
D000818:Animals; D013437:Carbon-Sulfur Lyases; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D008099:Liver / Q000201:enzymology*; D008190:Lyases / Q000302:isolation & purification* / Q000378:metabolism; D008297:Male; D008970:Molecular Weight; D051381:Rats; D011919:Rats, Inbred Strains; D013379:Substrate Specificity
D008190:Lyases; D013437:Carbon-Sulfur Lyases; C019969:S-alkylcysteine lyase