Insertion of the Fe_B cofactor in cNORs lacking metal inserting chaperones.

ABSTRACT: Cytochrome c-dependent nitric oxide reductase (cNOR) catalyzes the reduction of NO into nitrous oxide (N₂O), a strong greenhouse gas released from denitrifying microorganisms. The cNOR active site holds an essential non-heme iron, Fe_B, inserted using the chaperone complex NorQD. However, in Thermus thermophilus, the cNOR (TtcNOR) cluster lacks the norQD genes. Here we investigated Fe_B insertion into TtcNOR and characterized and compared TtcNOR expressed in Escherichia coli to that natively produced. We show that Fe_B is present in the natively produced TtcNOR only. Analysis of cNOR operon sequences suggests that a hydrophilic K-pathway analogue is present in cNORs that do not rely on NorQD for iron insertion. We discuss the implications of our dat

SUBMITTER: Appelgren S 

PROVIDER: S-EPMC12067857 | biostudies-literature | 2025 May

REPOSITORIES: biostudies-literature