In agreement with the results in S. Typhimurium, the loss of clpB by A. baumannii makes the microbe more susceptible to killing by macrophages than did the deletion of clpA. Similarly, the expression of the Ehrlichia chafeensis clpB gene is upregulated following infection of macrophages [51], indicating an important role of ClpB protein under oxidative stress. Here, TBX22 is linked to infection.