title: Localization of Chlamydia trachomatis hypothetical protein CT311 in host cell cytoplasm.
abstract: The chlamydia-specific hypothetical protein CT311 was detected both inside and outside of the chlamydial inclusions in Chlamydia trachomatis-infected cells. The extra-inclusion CT311 molecules were distributed in the host cell cytoplasm with a pattern similar to that of CPAF, a known Chlamydia-secreted protease. The detection of CT311 was specific since the anti-CT311 antibody labeling was only removed by absorption with CT311 but not CPAF fusion proteins. In addition, both anti-CT311 and anti-CPAF antibodies only detected their corresponding endogenous proteins without cross-reacting with each other or any other antigens in the whole cell lysates of C. trachomatis-infected cells. Although both CT311 and CPAF proteins were first detected 12 h after infection, localization of CT311 into host cell cytosol was delayed until 24 h while CPAF secretion into host cell cytosol was already obvious by 18 h after infection. The host cell cytosolic localization of CT311 was further confirmed in human primary cells. CT311 was predicted to contain an N-terminal secretion signal sequence and the CT311 signal sequence directed secretion of PhoA into bacterial periplasmic region in a heterologous assay system, suggesting that a sec-dependent pathway may play a role in the secretion of CT311 into host cell cytosol. This hypothesis is further supported by the observation that secretion of CT311 in Chlamydia-infected cells was blocked by a C16 compound known to inhibit signal peptidase I. These findings have provided important molecular information for further understanding the C. trachomatis pathogenic mechanisms.
authors: Department of Microbiology and Immunology, University of Texas Health Science Center at San Antonio, 7703 Floyd Curl Drive, San Antonio, TX 78229, USA.
authors: Lei
authors: L
authors: Lei
authors: Manli
authors: M
authors: Qi
authors: Nicole
authors: N
authors: Budrys
authors: Robert
authors: R
authors: Schenken
authors: Guangming
authors: G
authors: Zhong
references: Infect Immun. 2004 Jan;72(1):451-60
references: 14688126
references: J Exp Med. 2000 May 1;191(9):1525-34
references: 10790427
references: Proc Natl Acad Sci U S A. 1997 Dec 9;94(25):13856-61
references: 9391117
references: Microbiology (Reading). 2011 Apr;157(Pt 4):1134-1144
references: 21233161
references: Proc Natl Acad Sci U S A. 2004 Jul 6;101(27):9947-8
references: 15226494
references: Curr Opin Microbiol. 2008 Feb;11(1):53-9
references: 18299248
references: Mol Microbiol. 2006 Jul;61(1):142-50
references: 16824101
references: Infect Immun. 2006 Aug;74(8):4826-40
references: 16861671
references: FEMS Immunol Med Microbiol. 2009 Oct;57(1):46-58
references: 19682078
references: Cell Microbiol. 2005 Jun;7(6):825-36
references: 15888085
references: Cell Microbiol. 2007 Oct;9(10):2417-30
references: 17532760
references: Trends Microbiol. 1994 May;2(5):157-64
references: 8055179
references: J Immunol. 2010 Aug 1;185(3):1670-80
references: 20581152
references: Mol Microbiol. 2009 Jun;72(6):1423-37
references: 19460098
references: J Biol Chem. 2004 Mar 5;279(10):9409-16
references: 14676189
references: J Exp Med. 2001 Apr 16;193(8):935-42
references: 11304554
references: J Bacteriol. 1970 Jan;101(1):278-85
references: 5413965
references: Microbes Infect. 2006 May;8(6):1579-91
references: 16698305
references: Cell Host Microbe. 2008 Dec 11;4(6):529-42
references: 19064254
references: Sex Transm Dis. 1990 Jul-Sep;17(3):115-21
references: 2247800
references: Trends Microbiol. 2009 Oct;17(10):467-74
references: 19765998
references: J Bacteriol. 2011 May;193(10):2498-509
references: 21441519
references: Infect Immun. 2008 Sep;76(9):3940-50
references: 18591235
references: Mol Microbiol. 1995 Feb;15(4):617-26
references: 7783634
references: Proc Natl Acad Sci U S A. 1995 May 23;92(11):4877-81
references: 7761416
references: Microbes Infect. 2002 Mar;4(3):333-40
references: 11909744
references: J Exp Med. 1998 Feb 16;187(4):487-96
references: 9463399
references: Infect Immun. 2008 Feb;76(2):515-22
references: 18025098
references: Trends Microbiol. 2003 Jan;11(1):44-51
references: 12526854
references: Semin Immunopathol. 2011 Sep;33(5):395-408
references: 21153593
references: J Immunol. 2010 Mar 1;184(5):2602-10
references: 20124098
references: Mol Microbiol. 2003 May;48(3):671-83
references: 12694613
references: Proc Natl Acad Sci U S A. 2008 Jul 8;105(27):9379-84
references: 18591669
references: Microbiology (Reading). 2010 Oct;156(Pt 10):3031-3040
references: 20522495
references: Microbiol Mol Biol Rev. 2010 Mar;74(1):81-94
references: 20197500
references: Infect Immun. 2008 Aug;76(8):3415-28
references: 18474640
references: Proc Natl Acad Sci U S A. 2004 Jul 6;101(27):10166-71
references: 15199184
references: Infect Immun. 2006 Mar;74(3):1490-9
references: 16495519
references: Mol Microbiol. 2005 Jun;56(6):1636-47
references: 15916612
references: Infect Immun. 2004 Jul;72(7):3863-8
references: 15213128
references: Arch Biochem Biophys. 2009 May 1;485(1):16-23
references: 19388144
references: Ann Intern Med. 2006 Oct 17;145(8):564-72
references: 17043338
references: Infect Immun. 2010 Sep;78(9):3822-31
references: 20605984
references: J Biol Chem. 2006 Oct 20;281(42):31495-501
references: 16940052
references: Trends Microbiol. 1997 Jul;5(7):288-93
references: 9234512
references: Infect Immun. 2003 Feb;71(2):973-84
references: 12540580
references: J Exp Med. 1999 Jun 21;189(12):1931-8
references: 10377188
references: J Bacteriol. 1970 Dec;104(3):1332-7
references: 16559112
references: Cell Host Microbe. 2008 Aug 14;4(2):93-5
references: 18692768
references: Infect Immun. 2011 Jun;79(6):2193-203
references: 21422182
references: Cell Host Microbe. 2008 Aug 14;4(2):159-69
references: 18692775
references: J Biol Chem. 2011 Jan 14;286(2):1269-76
references: 21056982
references: J Infect. 2003 Jul;47(1):45-51
references: 12850162
references: Cell Microbiol. 2003 May;5(5):315-22
references: 12713490
references: Infect Immun. 2008 Jun;76(6):2746-57
references: 18391011
references: Infect Immun. 2010 Dec;78(12):5054-61
references: 20876296
references: Infect Immun. 2006 Nov;74(11):6479-86
references: 17057097
references: J Infect. 2006 Dec;53(6):408-14
references: 16490255