title: Localization and characterization of two putative TMH family proteins in Chlamydia psittaci.
abstract: Chlamydia psittaci (C. psittaci), an obligate intracellular agent of psittacosis, causes an atypical pneumonia in humans. The transmembrane head proteins (TMH) of C. psittaci, putatively belong to the Inc family and presumably play similar roles. CPSIT_0844 and CPSIT_0846 were the putative TMH proteins of C. psittaci. To identify these two proteins, antisera were raised with fusion proteins which were prokaryotic expressed in Escherichia coli and purified. By immunofluorescence assay, CPSIT_0844 and CPSIT_0846 were localized in the inclusion membrane of C. psittaci-infected cells. By RT-PCR and western blot analysis to detect the temporal expression, CPSIT_0844 and CPSIT_0846 were detected as early as 12h post-infection (p.i.) and 6h p.i., separately; meanwhile, in secretions monitored with immunofluorescence assay, these proteins were observed in the inclusion membrane at 18h p.i. and remained in the inclusion membrane throughout the growth cycle. CPSIT_0844 and CPSIT_0846 could specifically be recognized by the antiserum of C. psittaci but failed to react with the antiserums of Chlamydia trachomatis and Chlamydia pneumoniae, which is consistent with the fact that they had no significant orthologs in C. trachomatis and C. pneumoniae. These results revealed that CPSIT_0844 and CPSIT_0846, the putative TMH family proteins, might be unique to C. psittaci and could be used to diagnose the infection caused by C. psittaci. Moreover, CPSIT_0844 and CPSIT_0846 could induce the expression of the inflammatory cytokines IL-1β, IL-6 and TNF-α in THP-1 cells, which might contribute to chlamydia-induced inflammatory pathologies.
authors.affiliation: Institute of Pathogenic Biology, Medical College, University of South China, Hunan Provincial Key Laboratory for Special Pathogens Prevention and Control, Hengyang 421001, China; Department of Laboratory Medicine, The Second Affiliated Hospital of University of South China, Hengyang 421001, China.
authors.forename: Haiying
authors.initials: H
authors.lastname: Wu
authors.affiliation: Institute of Pathogenic Biology, Medical College, University of South China, Hunan Provincial Key Laboratory for Special Pathogens Prevention and Control, Hengyang 421001, China; Hunan Province Cooperative Innovation Center for Molecular Target New Drug Study, Hengyang 421001, China.
authors.forename: Chuan
authors.initials: C
authors.lastname: Wang
authors.affiliation: Institute of Pathogenic Biology, Medical College, University of South China, Hunan Provincial Key Laboratory for Special Pathogens Prevention and Control, Hengyang 421001, China.
authors.forename: Chuanhao
authors.initials: C
authors.lastname: Jiang
authors.affiliation: Institute of Pathogenic Biology, Medical College, University of South China, Hunan Provincial Key Laboratory for Special Pathogens Prevention and Control, Hengyang 421001, China; Hunan Province Cooperative Innovation Center for Molecular Target New Drug Study, Hengyang 421001, China.
authors.forename: Yafeng
authors.initials: Y
authors.lastname: Xie
authors.affiliation: Institute of Pathogenic Biology, Medical College, University of South China, Hunan Provincial Key Laboratory for Special Pathogens Prevention and Control, Hengyang 421001, China.
authors.forename: Liangzhuan
authors.initials: L
authors.lastname: Liu
authors.affiliation: Institute of Pathogenic Biology, Medical College, University of South China, Hunan Provincial Key Laboratory for Special Pathogens Prevention and Control, Hengyang 421001, China.
authors.forename: Ying
authors.initials: Y
authors.lastname: Song
authors.affiliation: Institute of Pathogenic Biology, Medical College, University of South China, Hunan Provincial Key Laboratory for Special Pathogens Prevention and Control, Hengyang 421001, China.
authors.forename: Xiaohua
authors.initials: X
authors.lastname: Ma
authors.affiliation: Institute of Pathogenic Biology, Medical College, University of South China, Hunan Provincial Key Laboratory for Special Pathogens Prevention and Control, Hengyang 421001, China. Electronic address: yimouwu@sina.com.
authors.forename: Yimou
authors.initials: Y
authors.lastname: Wu
mesh_terms: D001425:Bacterial Outer Membrane Proteins / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D001426:Bacterial Proteins / Q000235:genetics / Q000276:immunology* / Q000302:isolation & purification* / Q000494:pharmacology; D002690:Chlamydia Infections / Q000175:diagnosis / Q000276:immunology / Q000382:microbiology; D002691:Chlamydophila psittaci / Q000235:genetics / Q000378:metabolism*; D003001:Cloning, Molecular; D016207:Cytokines / Q000096:biosynthesis; D004926:Escherichia coli / Q000235:genetics; D005455:Fluorescent Antibody Technique / Q000379:methods; D005798:Genes, Bacterial; D006367:HeLa Cells; D006801:Humans; D007106:Immune Sera / Q000276:immunology / Q000302:isolation & purification; D009956:Psittacosis / Q000382:microbiology; D011994:Recombinant Proteins / Q000235:genetics; D014409:Tumor Necrosis Factor-alpha / Q000096:biosynthesis
chemical_list: D001425:Bacterial Outer Membrane Proteins; D001426:Bacterial Proteins; D016207:Cytokines; D007106:Immune Sera; D011994:Recombinant Proteins; D014409:Tumor Necrosis Factor-alpha
keywords: CPSIT_0844; CPSIT_0846; Chlamydia psittaci; Inclusion membrane protein; Putative TMH family protein