IUBMB Enzyme Nomenclature


Accepted name: carnosine synthase

Reaction: ATP + L-histidine + β-alanine = ADP + phosphate + carnosine

Glossary: carnosine = N-β-alanyl-L-histidine

Other name(s): carnosine synthetase; carnosine-anserine synthetase; homocarnosine-carnosine synthetase; carnosine-homocarnosine synthetase; L-histidine:β-alanine ligase (AMP-forming) (incorrect)

Systematic name: L-histidine:β-alanine ligase (ADP-forming)

Comments: This enzyme was thought to form AMP [1,2], but studies with highly purified enzyme proved that it forms ADP [4]. Carnosine is a dipeptide that is present at high concentrations in skeletal muscle and the olfactory bulb of vertebrates [3]. It is also found in the skeletal muscle of some invertebrates. The enzyme can also catalyse the formation of homocarnosine from 4-aminobutanoate and L-histidine, with much lower activity [4].

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, CAS registry number: 9023-61-4


1. Kalyankar, G.D. and Meister, A. Enzymatic synthesis of carnosine and related β-alanyl and γ-aminobutyryl peptides. J. Biol. Chem. 234 (1959) 3210-3218. [PMID: 14404206]

2. Stenesh, J.J. and Winnick, T. Carnosine-anserine synthetase of muscle. 4. Partial purification of the enzyme and further studies of β-alanyl peptide synthesis. Biochem. J. 77 (1960) 575-581. [PMID: 16748858]

3. Crush, K.G. Carnosine and related substances in animal tissues. Comp. Biochem. Physiol. 34 (1970) 3-30. [PMID: 4988625]

4. Drozak, J., Veiga-da-Cunha, M., Vertommen, D., Stroobant, V. and Van Schaftingen, E. Molecular identification of carnosine synthase as ATP-grasp domain-containing protein 1 (ATPGD1). J. Biol. Chem. 285 (2010) 9346-9356. [PMID: 20097752]

[EC created 1965, modified 2010]

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