Cysteine-S-conjugate beta-lyase
In enzymology, a cysteine-S-conjugate beta-lyase (EC 4.4.1.13) is an enzyme that catalyzes the chemical reaction
- RS-CH2-CH(NH3+)COO- RSH + NH3 + pyruvate
| cysteine-S-conjugate beta-lyase | |||||||||
|---|---|---|---|---|---|---|---|---|---|
| Identifiers | |||||||||
| EC number | 4.4.1.13 | ||||||||
| CAS number | 68652-57-3 | ||||||||
| Databases | |||||||||
| IntEnz | IntEnz view | ||||||||
| BRENDA | BRENDA entry | ||||||||
| ExPASy | NiceZyme view | ||||||||
| KEGG | KEGG entry | ||||||||
| MetaCyc | metabolic pathway | ||||||||
| PRIAM | profile | ||||||||
| PDB structures | RCSB PDB PDBe PDBsum | ||||||||
| Gene Ontology | AmiGO / QuickGO | ||||||||
| |||||||||
Hence, this enzyme has one substrate, [[RS-CH<sub>2</sub>-CH(NH<sub>3</sub>+)COO-]], but 3 products: RSH, NH3, and pyruvate.
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-S-conjugate thiol-lyase (deaminating; pyruvate-forming). Other names in common use include cysteine conjugate beta-lyase, glutamine transaminase K/cysteine conjugate beta-lyase, and L-cysteine-S-conjugate thiol-lyase (deaminating). It employs one cofactor, pyridoxal phosphate.
Structural studies
As of late 2007, 3 structures have been solved for this class of enzymes, with PDB accession codes 1W7L, 1W7M, and 1W7N.
References
- Tateishi M, Suzuki S, Shimizu H (1978). "Cysteine conjugate beta-lyase in rat liver. A novel enzyme catalyzing formation of thiol-containing metabolites of drugs". J. Biol. Chem. 253 (24): 8854–9. PMID 721818.