One fold, two functions: cytochrome P460 and cytochrome c'-β from the methanotroph Methylococcus capsulatus (Bath).

ABSTRACT: Nature is adept at utilising highly similar protein folds to carry out very different functions, yet the mechanisms by which this functional divergence occurs remain poorly characterised. In certain methanotrophic bacteria, two homologous pentacoordinate c-type heme proteins have been identified: a cytochrome P460 (cyt P460) and a cytochrome c'-β (cyt cp-β). Cytochromes P460 are able to convert hydroxylamine to nitrous oxide (N₂O), a potent greenhouse gas. This reactivity is similar to that of hydroxylamine oxidoreductase (HAO), which is a key enzyme in nitrifying and methanotrophic bacteria. Cyt P460 and HAO both have unusual protein-heme cross-links, formed by a Tyr residue in HAO and a Lys in cyt P460. In contrast, cyts cp-β (the only known cytochromes c' with a

SUBMITTER: Adams HR 

PROVIDER: S-EPMC6427953 | biostudies-literature | 2019 Mar

REPOSITORIES: biostudies-literature