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Published on: January 9, 2019
Chlamydia protease-like activity factor (CPAF): characterization of proteolysis activity in vitro and development of
Maria M Bednar1, Ine Jorgensen, Raphael H Valdivia
1Department of Chemistry, Duke University, Duke University Medical Center, Durham, North Carolina 27708, United States.
Abstract:
During infection of epithelial cells, the obligate intracellular pathogen Chlamydia trachomatis secretes the serine protease Chlamydia protease-like activity factor (CPAF) into the host cytosol to regulate a range of host cellular processes through targeted proteolysis. Here we report the development of an in vitro assay for the enzyme and the discovery of a cell-permeable CPAF zymogen-based peptide inhibitor with nanomolar inhibitory affinity. Treating C. trachomatis-infected HeLa cells with this inhibitor prevented CPAF cleavage of the intermediate filament vimentin and led to the loss of vimentin cage surrounding the intracellular vacuole. Because Chlamydia is a genetically intractable organism, this inhibitor may serve as a tool for understanding the role of CPAF in pathogenesis.
