Structure–function characterization reveals new catalytic diversity in the galactose oxidase and glyoxal oxidase family

Yin, DeLu; Urresti, Saioa; Lafond, Mickael; Johnston, Esther M.; Derikvand, Fatemeh; Ciano, Luisa; Berrin, Jean-Guy; Henrissat, Bernard; Walton, Paul H.; Davies, Gideon J.; Brumer, Harry

Abstract

Alcohol oxidases, including carbohydrate oxidases, have a long history of research that has generated fundamental biological understanding and biotechnological applications. Despite a long history of study, the galactose 6-oxidase/glyoxal oxidase family of mononuclear copper-radical oxidases, Auxiliary Activity Family 5 (AA5), is currently represented by only very few characterized members. Here we report the recombinant production and detailed structure–function analyses of two homologues from the phytopathogenic fungi Colletotrichum graminicola and C. gloeosporioides, CgrAlcOx and CglAlcOx, respectively, to explore the wider biocatalytic potential in AA5. EPR spectroscopy and crystallographic analysis confirm a common active-site structure vis-à-vis the archetypal galactose 6-oxidase from Fusarium graminearum. Strikingly, however, CgrAlcOx and CglAlcOx are essentially incapable of oxidizing galactose and galactosides, but instead efficiently catalyse the oxidation of diverse aliphatic alcohols. The results highlight the significant potential of prospecting the evolutionary diversity of AA5 to reveal novel enzyme specificities, thereby informing both biology and applications.

• Journal Article Type: Article
• Acceptance Date: Nov 16, 2015
• Online Publication Date: Dec 18, 2015
• Publication Date: 2015-12
• Deposit Date: Feb 13, 2020
• Publicly Available Date: Feb 21, 2020
• Journal: Nature Communications
• Electronic ISSN: 2041-1723
• Publisher: Nature Publishing Group
• Peer Reviewed: Peer Reviewed
• Volume: 6
• Issue: 1
• Article Number: 10197
• DOI: https://doi.org/10.1038/ncomms10197
• Public URL: https://nottingham-repository.worktribe.com/output/3829518
• Publisher URL: https://www.nature.com/articles/ncomms10197
• Additional Information: Received: 23 June 2015; Accepted: 16 November 2015; First Online: 18 December 2015; : The authors declare no competing financial interests.