Objective:To identify and validate secreted effector proteins of Chlamydia psittaci ( C. psittaci) through bioinformatic prediction and experimental verification, and to characterize their subcellular localization in host cells. Methods:Potential effector proteins were predicted using bioinformatics tools. Candidate effectors were fused to β-lactamase through the constructed expression vectors, and these vectors were transformed into C. psittaci. The secretion of these candidate effectors was evaluated by β-lactamase translocation assays. Eukaryotic expression vectors of confirmed effectors were transfected into host cells to determine their intracellular localization patterns. Results:Bioinformatic analysis identified 29 candidate effector proteins. Experimental validation confirmed the secretion of five effectors, with four exhibiting cytoplasmic localization and one displaying nuclear localization in host cells.Conclusion:This study characterizes five novel C. psittaci secreted effector proteins, providing critical insights for investigating the molecular pathogenesis of psittacosis.

Objective:To identify and validate secreted effector proteins of Chlamydia psittaci ( C. psittaci) through bioinformatic prediction and experimental verification, and to characterize their subcellular localization in host cells. Methods:Potential effector proteins were predicted using bioinformatics tools. Candidate effectors were fused to β-lactamase through the constructed expression vectors, and these vectors were transformed into C. psittaci. The secretion of these candidate effectors was evaluated by β-lactamase translocation assays. Eukaryotic expression vectors of confirmed effectors were transfected into host cells to determine their intracellular localization patterns. Results:Bioinformatic analysis identified 29 candidate effector proteins. Experimental validation confirmed the secretion of five effectors, with four exhibiting cytoplasmic localization and one displaying nuclear localization in host cells.Conclusion:This study characterizes five novel C. psittaci secreted effector proteins, providing critical insights for investigating the molecular pathogenesis of psittacosis.