An efficient biocatalytic synthesis of imidazole-4-acetic acid

Objective To develop a new and efficient biocatalytic synthesis method of imidazole-4-acetic acid (IAA) from l -histidine ( l -His). Results l -His was converted to imidazole-4-pyruvic acid (IPA) by an Escherichia coli whole-cell biocatalyst expressing membrane-bound l -amino acid deaminase (m l -AAD) from Proteus vulgaris firstly. The obtained IPA was subsequently decarboxylated to IAA under the action of H 2 O 2 . Under optimum conditions, 34.97 mM IAA can be produced from 50 mM l -His, with a yield of 69.9%. Conclusions Compared to the traditional chemical synthesis, this biocatalytic method for IAA production is not only environmentally friendly, but also more cost effective, thus being promising for industrial IAA production.