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Comparative structural analysis provides new insights into the function of R2-like ligand-binding oxidase.

ABSTRACT: R2-like ligand-binding oxidase (R2lox) is a ferritin-like protein that harbours a heterodinuclear manganese-iron active site. Although R2lox function is yet to be established, the enzyme binds a fatty acid ligand coordinating the metal centre and catalyses the formation of a tyrosine-valine ether cross-link in the protein scaffold upon O₂ activation. Here, we characterized the ligands copurified with R2lox by mass spectrometry-based metabolomics. Moreover, we present the crystal structures of two new homologs of R2lox, from Saccharopolyspora erythraea and Sulfolobus acidocaldarius, at 1.38 Å and 2.26 Å resolution, respectively, providing the highest resolution structure for R2lox, as well as new insights into putative mechanisms regulating the function of the enzyme.

SUBMITTER: Diamanti R

PROVIDER: S-EPMC9314684 | biostudies-literature | 2022 Jun

REPOSITORIES: biostudies-literature

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Comparative structural analysis provides new insights into the function of R2-like ligand-binding oxidase.

Diamanti Riccardo R Srinivas Vivek V Johansson Annika I AI Nordström Anders A Griese Julia J JJ Lebrette Hugo H Högbom Martin M

FEBS letters 20220304 12

R2-like ligand-binding oxidase (R2lox) is a ferritin-like protein that harbours a heterodinuclear manganese-iron active site. Although R2lox function is yet to be established, the enzyme binds a fatty acid ligand coordinating the metal centre and catalyses the formation of a tyrosine-valine ether cross-link in the protein scaffold upon O<sub>2</sub> activation. Here, we characterized the ligands copurified with R2lox by mass spectrometry-based metabolomics. Moreover, we present the crystal struc ...[more]

PMID: 35175627

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