A widely distributed diheme enzyme from Burkholderia that displays an atypically stable bis-Fe(IV) state.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 30846684.
- Also identified by DOI 10.1038/s41467-019-09020-4 and PMC identifier 6405878.
- Licence recorded as CC BY.
- The licence permits redistribution, so the abstract is shown in full and the full text is available from the publisher.
Abstract
Bacterial diheme peroxidases represent a diverse enzyme family with functions that range from hydrogen peroxide (H<sub>2</sub>O<sub>2</sub>) reduction to post-translational modifications. By implementing a sequence similarity network (SSN) of the bCCP_MauG superfamily, we present the discovery of a unique diheme peroxidase BthA conserved in all Burkholderia. Using a combination of magnetic resonance, near-IR and Mössbauer spectroscopies and electrochemical methods, we report that BthA is capable of generating a bis-Fe(IV) species previously thought to be a unique feature of the diheme enzyme MauG. However, BthA is not MauG-like in that it catalytically converts H<sub>2</sub>O<sub>2</sub> to water, and a 1.54-Å resolution crystal structure reveals striking differences between BthA and other superfamily members, including the essential residues for both bis-Fe(IV) formation and H<sub>2</sub>O<sub>2</sub> turnover. Taken together, we find that BthA represents a previously undiscovered class of diheme enzymes, one that stabilizes a bis-Fe(IV) state and catalyzes H<sub>2</sub>O<sub>2</sub> turnover in a mechanistically distinct manner.
Medical subject headings
- Bacterial Proteins
- Burkholderia
- Hemeproteins
- Peroxidases