IUBMB Enzyme Nomenclature


Accepted name: L-serine ammonia-lyase

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 [6]. 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, 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, 2-iminobutanoate/2-iminopropanoate deaminase. This reaction is also carried out by EC, 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]

[EC created 1961 as EC, transferred 2001 to EC, modified 2014]

Return to EC 4.3.1 home page
Return to EC 4.3 home page
Return to EC 4 home page
Return to Enzymes home page
Return to IUBMB Biochemical Nomenclature home page