6gsg

Publication Abstract from PubMed

Catechol oxidases and tyrosinases are coupled binuclear copper enzymes that oxidize various o-diphenolic compounds to corresponding o-quinones. Tyrosinases have an additional monooxygenation ability to hydroxylate monophenol to o-diphenol. It is still not clear what causes the difference in the catalytic activities. We solved a complex structure of Aspergillus oryzae catechol oxidase with resorcinol bound into the active site. Catalytic activity of A. oryzae catechol oxidase was studied, for the first time, by high-resolution FT-ICR mass spectrometry to shed light on the reaction mechanism. The enzyme was also found to catalyze monooxygenation of small phenolics, which provides a novel perspective for the discussion of differences in the catalytic activity between tyrosinases and catechol oxidases. According to the results, two binding modes for resorcinol are suggested and a reaction mechanism for coupled binuclear copper enzymes is discussed.

Unraveling substrate specificity and catalytic promiscuity of Aspergillus oryzae catechol oxidase.,Penttinen L, Rutanen C, Janis J, Rouvinen J, Hakulinen N Chembiochem. 2018 Sep 11. doi: 10.1002/cbic.201800387. PMID:30204291^[1]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.