Fig. 11

Models representing the role of H. pylori HP0377 in cytochrome c biogenesis and in oxidized protein folding. Following synthesis, apocytochrome c is translocated across the membrane by the Sec protein complex, and there it is oxidized by HP0231 (periplasmic dimeric oxidoreductase). Subsequently, its CXXCH motif is reduced by HP0377, and it is ligated to heme. Likely, as observed for other microorganisms, some molecules of the apocytochrome c are not oxidized and are directly ligated with heme (HP0231-independent pathway). Lack of HP0231 prevents HP0377 reduction by HP0265. A small portion of HP0377 is present in a dimeric form and potentially plays a role in the Dsb isomerization/reduction pathway. So far, the substrates of this pathway remains unknown