biostudies-literatureMaksimchuk KRNIAID NIH HHSe0147233https://www.ebi.ac.uk/biostudies/studies/S-EPMC4734761biostudies-literatureUnknown11(2)The need for more effective anti-chlamydial therapeutics has sparked research efforts geared toward further understanding chlamydial pathogenesis mechanisms. Recent studies have implicated the secreted chlamydial serine protease, chlamydial protease-like activity factor (CPAF) as potentially important for chlamydial pathogenesis. By mechanisms that remain to be elucidated, CPAF is directed to a discrete group of substrates, which are subsequently cleaved or degraded. While inspecting the previously solved CPAF crystal structure, we discovered that CPAF contains a cryptic N-terminal PSD95 Dlg ZO-1 (PDZ) domain spanning residues 106-212 (CPAF106-212). This PDZ domain is unique in that it bears minimal sequence similarity to canonical PDZ-forming sequences and displays little sequence and structural similarity to known chlamydial PDZ domains. We show that the CPAF106-212 sequence is homologous to PDZ domains of human tight junction proteins.PloS oneThe Chlamydia trachomatis Protease CPAF Contains a Cryptic PDZ-Like Domain with Similarity to Human Cell Polarity and Tight Junction PDZ-Containing Proteins.PMC4734761R01 AI107951R56 AI107951McCafferty DGMou RValdivia RHMaksimchuk KRAlser KAfalseThe Chlamydia trachomatis Protease CPAF Contains a Cryptic PDZ-Like Domain with Similarity to Human Cell Polarity and Tight Junction PDZ-Containing Proteins.The need for more effective anti-chlamydial therapeutics has sparked research efforts geared toward further understanding chlamydial pathogenesis mechanisms. Recent studies have implicated the secreted chlamydial serine protease, chlamydial protease-like activity factor (CPAF) as potentially important for chlamydial pathogenesis. By mechanisms that remain to be elucidated, CPAF is directed to a discrete group of substrates, which are subsequently cleaved or degraded. While inspecting the previously solved CPAF crystal structure, we discovered that CPAF contains a cryptic N-terminal PSD95 Dlg ZO-1 (PDZ) domain spanning residues 106-212 (CPAF106-212). This PDZ domain is unique in that it bears minimal sequence similarity to canonical PDZ-forming sequences and displays little sequence and structural similarity to known chlamydial PDZ domains. We show that the CPAF106-212 sequence is homologous to PDZ domains of human tight junction proteins.2016-01-01T00:00:00Z20162021-02-20T12:47:05Z2019-03-26T22:57:09ZS-EPMC47347612682955010.1371/journal.pone.0147233