CLPB and infection: ClpB mainly mediates tolerance to stressful conditions, including heat, oxidation, nutrient-depletion, contributing to metabolism, survival and growth of bacterial during infection (Fig. 9b).599 Guandine chloride (GdnHCl) is an organic salt, which efficiently inhibits the ATPase activity of ClpB in vitro by binding the NTD of ClpB.600,601 Despite its low binding affinity with a Kd value of approximately 600 μM, GdnHCl can serve as a useful tool for exploring the biological function of ClpB in pathogens (Table 5).