Reassessing the role of the secreted protease CPAF in Chlamydia trachomatis infection through genetic approaches.

SNAVELY, EA; KOKES, M; DUNN, JD; SAKA, HA; NGUYEN, BD; BASTIDAS, RJ; MCCAFFERTY, DG; VALDIVIA, RH

Pathogens and Disease

John Wiley & Sons

Año: 2014 p. 1 - 1

he secreted Chlamydia protease CPAF cleaves a defined set of mammalian and Chlamydia proteins in vitro. As a result, this protease has been proposed to modulate a range of bacterial and host cellular functions. However, it has recently come into question the extent to which many of its identified substrates constitute bona fide targets of proteolysis in infected host cell rather than artifacts of postlysis degradation. Here, we clarify the role played by CPAF in cellular models of infection by analyzing Chlamydia trachomatis mutants deficient for CPAF activity. Using reverse genetic approaches, we identified two C. trachomatis strains possessing nonsense, loss-of-function mutations in cpa (CT858) and a third strain containing a mutation in type II secretion (T2S) machinery that inhibited CPAF activity by blocking zymogen secretion and subsequent proteolytic maturation into the active hydrolase. HeLa cells infected with T2S- or CPAF-