Reaction: acetyl-CoA + L-2,4-diaminobutanoate = CoA + (2S)-4-acetamido-2-aminobutanoate
For diagram, click here
Other name(s): L-2,4-diaminobutyrate acetyltransferase; L-2,4-diaminobutanoate acetyltransferase; EctA; diaminobutyric acid acetyltransferase; DABA acetyltransferase; 2,4-diaminobutanoate acetyltransferase; DAB acetyltransferase; DABAcT
Systematic name: acetyl-CoA:L-2,4-diaminobutanoate N4-acetyltransferase
Comments: Requires Na+ or K+ for maximal activity [3]. Ornithine, lysine, aspartate, and α-, β- and γ-aminobutanoate cannot act as substrates [3]. However, acetyl-CoA can be replaced by propanoyl-CoA, although the reaction proceeds more slowly [3]. Forms part of the ectoine-biosynthesis pathway, the other enzymes involved being EC 2.6.1.76, diaminobutyrate—2-oxoglutarate transaminase and EC 4.2.1.108, ectoine synthase.
Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, PDB, CAS registry number: 130456-92-7
References:
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. Reshetnikov, A.S., Mustakhimov, I.I., Khmelenina, V.N. and Trotsenko, Y.A. Cloning, purification, and characterization of diaminobutyrate acetyltransferase from the halotolerant methanotroph Methylomicrobium alcaliphilum 20Z. Biochemistry (Mosc.) 70 (2005) 878-883. [PMID: 16212543]
4. 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]
5. 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]