Structure of BrxA from Staphylococcus aureus, a bacilliredoxin involved in redox homeostasis in Firmicutes.

Bacilliredoxins are small proteins that are involved in redox homeostasis in bacillithiol-producing bacteria. They reduce mixed bacillithiol disulfides on protected proteins through a disulfide-exchange reaction, restoring the thiol group on the target protein. Bacilliredoxins contain an unusual conserved CGC motif, and their exact catalytic mechanism remains unclear.