Reaction: L-serine = pyruvate + NH3 (overall reaction)
(1a) L-serine = 2-aminoprop-2-enoate + H2O
(1b) 2-aminoprop-2-enoate = 2-iminopropanoate (spontaneous)
(1c) 2-iminopropanoate + H2O = pyruvate + NH3 (spontaneous)
Other name(s): serine deaminase; L-hydroxyaminoacid dehydratase; L-serine deaminase; L-serine dehydratase; L-serine hydro-lyase (deaminating)
Systematic name: L-serine ammonia-lyase (pyruvate-forming)
Comments: Most enzymes that catalyse this reaction are pyridoxal-phosphate-dependent, although some enzymes contain an iron-sulfur cluster instead . The reaction catalysed by both types of enzymes involves the initial elimination of water to form an enamine intermediate (hence the enzyme’s original classification as EC 18.104.22.168, L-serine dehydratase), followed by tautomerization to an imine form and hydrolysis of the C-N bond. The latter reaction, which can occur spontaneously, is also be catalysed by EC 22.214.171.124, 2-iminobutanoate/2-iminopropanoate deaminase. This reaction is also carried out by EC 126.96.36.199, threonine ammonia-lyase, from a number of sources.
Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc, PDB, CAS registry number: 9014-27-1
1. Ramos, F. and Wiame, J.-M. Occurrence of a catabolic L-serine (L-threonine) deaminase in Saccharomyces cerevisiae. Eur. J. Biochem. 123 (1982) 571-576. [PMID: 7042346]
2. Simon, D., Hoshino, J. and Kröger, H. L-Serine dehydratase from rat liver. Purification and some properties. Biochim. Biophys. Acta 321 (1973) 361-368. [PMID: 4750769]
3. Suda, M. and Nakagawa, H. L-Serine dehydratase (rat liver). Methods Enzymol. 17B (1971) 346-351.
4. Sagers, R.D. and Carter, J. E. L-Serine dehydratase (Clostridium acidiurica). Methods Enzymol. 17B (1971) 351-356.
5. Robinson, W.G. and Labow, R. L-Serine dehydratase (Escherichia coli). Methods Enzymol. 17B (1971) 356-360.
6. Grabowski, R., Hofmeister, A.E. and Buckel, W. Bacterial L-serine dehydratases: a new family of enzymes containing iron-sulfur clusters. Trends Biochem. Sci. 18 (1993) 297-300. [PMID: 8236444]
7. Yamada, T., Komoto, J., Takata, Y., Ogawa, H., Pitot, H.C. and Takusagawa, F. Crystal structure of serine dehydratase from rat liver. Biochemistry 42 (2003) 12854-12865. [PMID: 14596599]