Abstract: Chlamydial protease-like activity factor (CPAF) is a Chlamydia trachomatis protease, which activity results in dampened host inflammation signaling, cytoskeletal remodeling, and suppressed neutrophil activation. We used series of bioinformatics to analyze and predict CPAF protein, physicochemical properties and hydrophobicity, signal peptide, subcellular localization, transmembrane protein structure, conserved region and N-glycosylation sites and phosphorylation sites, the secondary and tertiary structure, ligand-binding regions and small molecular compounds, B-/T-cell epitopes and the interacting proteins. CPAF, which consist of 601 amino acids, the relative molecular weight is 67 252.57 Da, the theoretical isoelectric point is 5.68. The CPAF protein contains a signal peptide and has non-transmembrane regions. The conserved domain of CPAF protein is located at 3～586 amino acid sequence and belongs to CPAF superfamily. The CPAF protein contains 1 N-glycosylation site and 53 phosphorylation sites. The secondary structure is mainly composed of irregular coiling and α-helix. The CPAF protein contains 14 ligand-binding sites, 20 B-cell epitopes, 4 conformational epitopes and several potential T-cell epitopes, and 5 potentially effective screening small molecule compounds. Meanwhile, CPAF may interact with 10 other proteins including htrA、pbpB、recC and so on. This study provides a theoretical basis for further researching the role of CPAF in the pathogenesis of Chlamydia trachomatis, which could be used as a target for vaccine developments and drug therapies.
Key words: Chlamydia trachomatis; CPAF; bioinformatics; structure; antigenic epitope
（Acta Laser Biology Sinica, 2023, 32(3): 247-258）