CdbC: a disulfide bond isomerase involved in the refolding of mycoloyltransferases in Corynebacterium glutamicum cells exposed to oxidative conditions.

This article focuses on the characterization of CdbC, a periplasmic disulfide bond isomerase encoded by the cdbC gene in Corynebacterium glutamicum, and its role in mycomembrane biosynthesis under oxidative conditions. The study demonstrates that CdbC efficiently catalyzes the refolding of misoxidized proteins, particularly interacting with mycoloyltransferases MytA and MytB, which are essential for proper mycomembrane formation. Overexpression of cdbC in a reducing environment leads to growth defects, altered cell morphology, increased cell surface hydrophobicity, and accumulation of trehalose monocorynomycolate, indicating mycomembrane deformation. These findings suggest that CdbC assists in maintaining cell envelope integrity by ensuring correct disulfide bond formation in secreted proteins during oxidative stress, thereby supporting cellular adaptation and viability.