Involved in the degradation of specific anti-sigma factors, specifically RsiT. Involved in the regulation of extracytoplasmic function sigma factors expression. Seems to play a role in the resistance to antimicrobial peptides. Required for colonization or survival in the host cecum. Reduced expression of the extracytoplasmic function sigma factor genes csfT and csfU (5-fold in mutant in comparison to wild-type). Decreased virulence (30-fold less virulent than the wild-type). Belongs to the protease PrsW family.