Effect of Cu(II) and Conserved Copper Binding Sites on the Multicopper Oxidase CopA and Characterization of BioMnO x .

Autor: Tang W; School of Chemical Science and Engineering, Tongji University, Shanghai, China.; Shanghai Key Laboratory of Chemical Assessment and Sustainability, Tongji University, Shanghai, China., Huang Z; School of Chemical Science and Engineering, Tongji University, Shanghai, China., Liu Y; School of Chemical Science and Engineering, Tongji University, Shanghai, China., Zeng X; School of Life Sciences and Technology, Tongji University, Shanghai, China.
Jazyk: angličtina
Zdroj: Proteins [Proteins] 2024 Sep 13. Date of Electronic Publication: 2024 Sep 13.
DOI: 10.1002/prot.26744
Abstrakt: The microbial manganese removal process is believed to consist of the catalytic oxidation of Mn(II) by manganese oxidase. In this study, the multicopper oxidase CopA was purified and exhibited high manganese oxidation activity in vitro, and it was found that Cu(II) can significantly enhance its manganese oxidation activity. Gene site-directed mutagenesis was used to mutate four conserved copper binding sites of CopA to obtain four mutant strains. The manganese removal efficiencies of the four strains were determined, and it was found that H120 is the catalytically active site of CopA. The loss of Cu(II) and the mutation of the conserved copper binding site H120 resulted in the loss of ethoxyformyl and quinone modifications, a reduction in the number of modifications, and a change in the position of modifications, eventually causing a decrease in protein activity from 85.87% to 70.1%. These results reveal that Cu(II) and H120 play an indispensable role in manganese oxidation by the multicopper oxidase CopA. X-ray photoelectron spectroscopy (XPS) analysis indicates that biogenic manganese oxides produced by strains and by CopA were both composed of MnO 2 and Mn 3 O 4 and that the average valence of Mn was 3.2.
(© 2024 Wiley Periodicals LLC.)
Databáze: MEDLINE
Externí odkaz: