The role of positive charged residue in the proton-transfer mechanism of two-domain laccase from Streptomyces griseoflavus Ac-993

• Type: Article in International Scientific Journal
• Date: 2022

Authors

Gabdulkhakov, A (Author) Other; Kolyadenko, I (Author) Other; Oliveira, P (Author) Other; Paula Tamagnini (Author) FCUP; Mikhaylina, A (Author) Other; Tishchenko, S (Author) Other

Journal

Title: Journal of Biomolecular Structure and Dynamics

Vol. 40

Pages: 8324-8331

ISSN: 0739-1102

Publisher: Taylor & Francis

Indexing

ISI Web of Knowledge - 2 Citations

Scopus - 1 Citation

Other information

Authenticus ID: P-00T-VJM

DOI: 10.1080/07391102.2021.1911852

Abstract (EN): Multi-copper oxidases are capable of coupling the one-electron oxidation of four substrate equivalents to the four-electron reduction of dioxygen to two molecules of water. This process takes place at the trinuclear copper center of the enzymes. Previously, the main catalytic stages for three-domain (3D) laccases have been identified. However, for bacterial small two-domain (2D) laccases several questions remain to be answered. One of them is the nature of the protonation events upon the reductive cleavage of dioxygen to water. In 3D laccases, acidic residues play a key role in the protonation mechanisms. In this study, the role of the Arg240 residue, located within the T2 tunnel of 2D laccase from Streptomyces griseoflavus Ac-993, was investigated. X-ray structural analysis and kinetic characterization of two mutants, R240A and R240H, have provided support for a role of this residue in the protonation events. Communicated by Ramaswamy H. Sarma

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 8