A heme pocket aromatic quadrupole modulates gas binding to cytochrome c'-β: Implications for NO sensors.

ABSTRACT: The structural basis by which gas-binding heme proteins control their interactions with NO, CO, and O₂ is fundamental to enzymology, biotechnology, and human health. Cytochromes c' (cyts c') are a group of putative NO-binding heme proteins that fall into two families: the well-characterized four alpha helix bundle fold (cyts c'-α) and an unrelated family with a large beta-sheet fold (cyts c'-β) resembling that of cytochromes P460. A recent structure of cyt c'-β from Methylococcus capsulatus Bath revealed two heme pocket phenylalanine residues (Phe 32 and Phe 61) positioned near the distal gas-binding site. This feature, dubbed the "Phe cap," is highly conserved within the sequences of other cyts c'-β but is absent in their close homologs, the hydroxylamine-oxidizing cytochromes

SUBMITTER: Adams HR 

PROVIDER: S-EPMC10318465 | biostudies-literature | 2023 Jun

REPOSITORIES: biostudies-literature