IUBMB Enzyme Nomenclature


Accepted name: ectoine synthase

Reaction: N4-acetyl-L-2,4-diaminobutanoate = L-ectoine + H2O

For diagram, click here

Glossary: ectoine = (4S)-2-methyl-1,4,5,6-tetrahydropyrimidine-4-carboxylate

Other name(s): N-acetyldiaminobutyrate dehydratase; N-acetyldiaminobutanoate dehydratase; L-ectoine synthase; EctC; N4-acetyl-L-2,4-diaminobutanoate hydro-lyase; 4-N-acetyl-L-2,4-diaminobutanoate hydro-lyase; 4-N-acetyl-L-2,4-diaminobutanoate hydro-lyase (L-ectoine-forming)

Systematic name: N4acetyl-L-2,4-diaminobutanoate hydro-lyase (L-ectoine-forming)

Comments: Ectoine is an osmoprotectant that is found in halophilic eubacteria. This is the third enzyme in the ectoine-biosynthesis pathway, the other enzymes involved being EC, diaminobutyrate—2-oxoglutarate transaminase and EC, diaminobutyrate acetyltransferase [1,2].

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, CAS registry number:


1. Peters, P., Galinski, E.A. and Truper, H.G. The biosynthesis of ectoine. FEMS Microbiol. Lett. 71 (1990) 157-162.

2. Ono, H., Sawada, K., Khunajakr, N., Tao, T., Yamamoto, M., Hiramoto, M., Shinmyo, A., Takano, M. and Murooka, Y. Characterization of biosynthetic enzymes for ectoine as a compatible solute in a moderately halophilic eubacterium, Halomonas elongata. J. Bacteriol. 181 (1999) 91-99. [PMID: 9864317]

3. Kuhlmann, A.U. and Bremer, E. Osmotically regulated synthesis of the compatible solute ectoine in Bacillus pasteurii and related Bacillus spp. Appl. Environ. Microbiol. 68 (2002) 772-783. [PMID: 11823218]

4. Louis, P. and Galinski, E.A. Characterization of genes for the biosynthesis of the compatible solute ectoine from Marinococcus halophilus and osmoregulated expression in Escherichia coli. Microbiology 143 (1997) 1141-1149. [PMID: 9141677]

[EC created 2006]

Return to EC 4.2.1 home page
Return to EC 4.2 home page
Return to EC 4 home page
Return to Enzymes home page
Return to IUBMB Biochemical Nomenclature home page