Cytochromes P460 and c′‐beta; A new family of high‐spin cytochromes c

Abstract
Cytochromes‐P460 of Nitrosomonas europaea and Methylococcus capsulatus (Bath), and the cytochrome c′ of M. capsulatus, believed to be involved in binding or transformation of N‐oxides, are shown to represent an evolutionarily related new family of monoheme, ∼17 kDa, cytochromes c found in the genomes of diverse Proteobacteria. All members of this family have a predicted secondary structure predominantly of beta‐sheets in contrast to the predominantly alpha‐helical cytochromes c′ found in photoheterotrophic and denitrifying Proteobacteria.