Complex Oxidation of Apocytochromes c during Bacterial Cytochrome c Maturation

DsbA is a powerful oxidase that functions in the bacterial periplasm to introduce disulfide bonds in many proteins, including apocytochromesc . It has been well established that although DsbA is not essential, it plays a primary role in cytochromec maturation, based on studies in bacteria hosting several cytsc . Here, with cytc -richS. oneidensis as a research model, we show that this is not always the case. Moreover, we demonstrate that DsbB is also not essential for cytochromec maturation. These results underscore the need to identify oxidants other than DsbA/DsbB that are crucial in the oxidation of apocytsc in bacteria.