Reaction: L-selenocysteine + reduced acceptor = selenide + L-alanine + acceptor
Glossary: dithiothreitol = 1,4-bis(sulfanyl)butane-2,3-diol
Other name(s): selenocysteine reductase; selenocysteine β-lyase
Systematic name: L-selenocysteine selenide-lyase (L-alanine-forming)
Comments: A pyridoxal-phosphate protein. Dithiothreitol or 2-sulfanylethan-1-ol (2-mercaptoethanol) can act as the reducing agent in the reaction. The enzyme from animals does not act on cysteine, serine or chloroalanine [1,3], while the enzyme from bacteria shows activity with cysteine (cf. EC 2.8.1.7, cysteine desulfurase) [2].
Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, PDB, CAS registry number: 82047-76-5
References:
1. Esaki, N., Nakamura, T., Tanaka, H. and Soda, K. Selenocysteine lyase, a novel enzyme that specifically acts on selenocysteine. Mammalian distribution and purification and properties of pig liver enzyme. J. Biol. Chem. 257 (1982) 4386-4391. [PMID: 6461656]
2. Mihara, H., Kurihara, T., Yoshimura, T., Soda, K. and Esaki, N. Cysteine sulfinate desulfinase, a NIFS-like protein of Escherichia coli with selenocysteine lyase and cysteine desulfurase activities. Gene cloning, purification, and characterization of a novel pyridoxal enzyme. J. Biol. Chem. 272 (1997) 22417-22424. [PMID: 9278392]
3. Omi, R., Kurokawa, S., Mihara, H., Hayashi, H., Goto, M., Miyahara, I., Kurihara, T., Hirotsu, K. and Esaki, N. Reaction mechanism and molecular basis for selenium/sulfur discrimination of selenocysteine lyase. J. Biol. Chem. 285 (2010) 12133-12139. [PMID: 20164179]