Staphylococcal ClpXP protease targets the cellular antioxidant system to eliminate fitness-compromised cells in stationary phase
Abdulelah A. Alqarzaee, Sujata S. Chaudhari, Mohammad Mazharul Islam, Vikas Kumar, Matthew C. Zimmerman, Rajib Saha, Kenneth W. Bayles, Dorte Frees, Vinai C. Thomas
Abstract
Significance Bacterial populations that transition to stationary phase can efficiently maintain their competitive fitness potential even when subject to various stressors that damage cellular macromolecules. However, the mechanism remains unclear. Here, we show that stationary phase staphylococci that harbor damaged proteins in their cytoplasm undergo a regulated form of cell death to maintain the competitive fitness potential of the bacterial population. The activation of cell death is achieved by the down-regulation or degradation of cellular antioxidant proteins by the ATP-dependent ClpXP protease, which usually functions to maintain protein quality control in cells.