IUBMB Enzyme Nomenclature


Accepted name: ectoine synthase

Reaction: (2S)-4-acetamido-2-aminobutanoate = L-ectoine + H2O

For diagram of reaction click here.

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

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

Systematic name: (2S)-4-acetamido-2-aminobutanoate (L-ectoine-forming)

Comments: Ectoine is an osmoprotectant that is found in halophilic eubacteria. This enzyme is part of the ectoine biosynthesis pathway and only acts in the direction of ectoine formation. cf. EC, ectoine hydrolase.

Links to other databases: BRENDA, EXPASY, KEGG, MetaCyc, PDB, 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]

5. Schwibbert, K., Marin-Sanguino, A., Bagyan, I., Heidrich, G., Lentzen, G., Seitz, H., Rampp, M., Schuster, S.C., Klenk, H.P., Pfeiffer, F., Oesterhelt, D. and Kunte, H.J. A blueprint of ectoine metabolism from the genome of the industrial producer Halomonas elongata DSM 2581 T. Environ. Microbiol. 13 (2011) 1973-1994. [PMID: 20849449]

[EC created 2006, modified 2017]

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