Regio- and Stereospecific Conversion of 4-Alkylphenols by the Covalent Flavoprotein Vanillyl-Alcohol Oxidase

Regio- and stereospecific conversion of 4-alkylphenols by the covalent flavoprotein vanillyl-alcohol oxidase.

The regio- and stereospecific conversion of prochiral 4-alkylphenols by the covalent flavoprotein vanillyl-alcohol oxidase was investigated. The enzyme was active, with 4-alkylphenols bearing aliphatic side chains of up to seven carbon atoms. Optimal catalytic efficiency occurred with 4-ethylphenol and 4-n-propylphenols. These short-chain 4-alkylphenols are stereoselectively hydroxylated to the...

Enigmatic Gratuitous Induction of the Covalent Flavoprotein Vanillyl-Alcohol Oxidase in Penicillium simplicissimum.

When Penicillium simplicissimum is grown on veratryl alcohol, anisyl alcohol, or 4-(methoxymethyl)phenol, an intracellular covalent flavin-containing vanillyl-alcohol oxidase is induced. The induction is highest (up to 5% of total protein) during the growth phase. In addition to vanillyl-alcohol oxidase, an intracellular catalase-peroxidase is induced. Induction of vanillyl-alcohol oxidase in P...

Direction of the reactivity of vanillyl-alcohol oxidase with 4-alkylphenols.

The covalent flavoprotein vanillyl-alcohol oxidase (VAO) predominantly converts short-chain 4-alkylphenols, like 4-ethylphenol, to (R)-1-(4'-hydroxyphenyl)alcohols and medium-chain 4-alkylphenols, like 4-butylphenol, to 1-(4'-hydroxyphenyl)alkenes. Crystallographic studies have indicated that the active site residue Asp170 is involved in determining the efficiency of substrate hydroxylation. To...

Covalent flavinylation of vanillyl-alcohol oxidase is an autocatalytic process.

Vanillyl-alcohol oxidase (VAO; EC 1.1.3.38) contains a covalently 8alpha-histidyl bound FAD, which represents the most frequently encountered covalent flavin-protein linkage. To elucidate the mechanism by which VAO covalently incorporates the FAD cofactor, apo VAO was produced by using a riboflavin auxotrophic Escherichia coli strain. Incubation of apo VAO with FAD resulted in full restoration ...

University of Groningen Enigmatic Gratuitous Induction of the Covalent Flavoprotein Vanillyl-Alcohol Oxidase in Penicillium simplicissimum Fraaije, Marco; Pikkemaat,