| cysteine lyase | |
| Ec Number: | 4.4.1.10 |
| Cas Number: | 9079-86-1 |
| Go Code: | 0047803 |
The enzyme cysteine lyase (EC 4.4.1.10) [1] catalyzes the chemical reaction
L-cysteine + sulfite
\rightleftharpoons
This enzyme belongs to the family of lyases, specifically the class of carbon-sulfur lyases. The systematic name of this enzyme class is L-cysteine hydrogen-sulfide-lyase (adding sulfite; L-cysteate-forming). Other names in common use include cysteine (sulfite) lyase, and L-cysteine hydrogen-sulfide-lyase (adding sulfite). This enzyme participates in cysteine and taurine metabolism. It employs one cofactor, pyridoxal phosphate.
Genes encoding cysteine lyase (CL) originated around 300 million years ago by a tandem gene duplication and neofunctionalization of cystathionine β-lyase (CBS) shortly after the split of mammalian and reptilian lineages. CL genes are found only in Sauropsida where they are involved in a metabolic pathway for sulfur metabolism in the chicken egg.[2]