Spectral and catalytic properties of aryl-alcohol oxidase, a fungal flavoenzyme acting on polyunsaturated alcohols

• DOI: 10.1042/bj20041903
• Publication Date: 2005-07-27T13:22:54Z
• Authors: Patricia Ferreira; Milagros Medina; Francisco Guillén; María Jesús Martínez; Willem J. H. Van ...; Ángel T. Martínez
• Keywords: Benzyl alcohol

Spectral and catalytic properties of the flavoenzyme AAO (aryl-alcohol oxidase) from Pleurotus eryngii were investigated using recombinant enzyme. Unlike most flavoprotein oxidases, does not thermodynamically stabilize a flavin semiquinone radical forms no sulphite adduct. catalyses oxidative dehydrogenation wide range unsaturated primary alcohols with hydrogen peroxide production. This differentiates enzyme VAO (vanillyl-alcohol oxidase), which is specific for phenolic compounds. Moreover, optimally active in pH 5-6, whereas has an optimum at 10. Kinetic studies showed that p-anisyl alcohol 2,4-hexadien-1-ol. converts m- p-chlorinated benzyl similar rate as it alcohol, but introduction p-methoxy substituent increases reaction approx. 5-fold. also exhibits low activity on aromatic aldehydes. 19F NMR analysis fluorinated benzaldehydes are converted into corresponding benzoic acids. Inhibition revealed site can bind ligands, chavicol (4-allylphenol) p-anisic (4-methoxybenzoic) acid being best competitive inhibitors. Uncompetitive inhibition was observed 4-methoxybenzylamine. The described above render unique oxidase. possible mechanism binding oxidation substrates discussed light results kinetic studies.