The flavoenzyme vanillyl-alcohol oxidase (VAO) catalyzes the conversion of 4-alkylphenols through the initial formation of p-quinone methide intermediates. These electrophilic species are stereospecifically attacked by water to yield (R)-1-(4'- hydroxyphenyl) alcohols or rearranged in a competing reaction to 1-(4'-hydroxyphenyl)alkenes. Here, we show that the product spectrum of VAO can be controlled by medium engineering. When the enzymatic conversion of 4-propylphenol was performed in organic solvent, the concentration of the alcohol decreased and the concentration of the cis-alkene, but not the trans-alkene, increased. This change in selectivity occurred in both toluene and acetonitrile and was dependent on the water activity of the reaction medium. A similar shift in alcohol/cis-alkene product ratio was observed when the VAO-mediated conversion of 4- propylphenol was performed in the presence of monovalent anions that bind specifically near the enzyme active site. (C) 2001 Federation of European Biochemical Societies.
- vanillyl-alcohol oxidase
- medium engineering
- quinone methide
- organic- solvents
van den Heuvel, R. H. H., Partridge, J., Laane, C., Halling, P. J., & van Berkel, W. J. H. (2001). Tuning of the product spectrum of vanillyl-alcohol oxidase by medium engineering. FEBS Letters, 503(2-3), 213-216. https://doi.org/10.1016/S0014-5793(01)02658-8