EC 126.96.36.199 - 1-aminocyclopropane-1-carboxylate deaminase
IntEnz Enzyme Nomenclature
1-aminocyclopropane carboxylic acid deaminase
- (1) 1-aminocyclopropane-1-carboxylate + H2O = 2-oxobutanoate + NH3
- (1a) 1-aminocyclopropane-1-carboxylate = 2-aminobut-2-enoate
- (1b) 2-aminobut-2-enoate = 2-iminobutanoate (spontaneous)
- (1c) 2-iminobutanoate + H2O = 2-oxobutanoate + NH3 (spontaneous)
A pyridoxal 5'-phosphate enzyme. The enzyme, found in certain soil bacteria and fungi, catalyses the ring opening of 1-aminocyclopropane-1-carboxylate, the immediate precursor to ethylene, an important plant hormone that regulates fruit ripening and other processes. The enzyme releases an unstable enamine product that tautomerizes to an imine form, which undergoes spontaneous hydrolytic deamination. The enzyme has been used to make fruit ripening dependent on externally added ethylene, as it removes the substrate for endogenous ethylene formation.
Links to other databases
Metabolism of 1-aminocyclopropane-1-carboxylic acid.Agric. Biol. Chem. 42: 1825-1831 (1978).
Crystal structure of 1-aminocyclopropane-1-carboxylate deaminase from Hansenula saturnus.J. Biol. Chem. 275: 34557-34565 (2000). [PMID: 10938279]
Mechanistic studies of 1-aminocyclopropane-1-carboxylate deaminase: characterization of an unusual pyridoxal 5'-phosphate-dependent reaction.Biochemistry 50: 1950-1962 (2011). [PMID: 21244019]
[EC 188.8.131.52 created 1981 as EC 184.108.40.206, transferred 2002 to EC 220.127.116.11, modified 2014]