title: Golgi fragmentation and sphingomyelin transport to Chlamydia trachomatis during penicillin-induced persistence do not depend on the cytosolic presence of the chlamydial protease CPAF.
abstract: Chlamydia grows inside a cytosolic vacuole (the inclusion) that is supplied with nutrients by the host through vesicular and non-vesicular transport. It is unclear in many respects how Chlamydia organizes this transport. One model posits that the Chlamydia-induced fragmentation of the Golgi-apparatus is required for normal transport processes to the inclusion and for chlamydial development, and the chlamydial protease CPAF has been controversially implicated in Golgi-fragmentation. We here use a model of penicillin-induced persistence of infection with Chlamydia trachomatis to test this link. Under penicillin-treatment the inclusion grew in size for the first 24 h but after that growth was severely reduced. Penicillin did not reduce the number of infected cells with fragmented Golgi-apparatus, and normal Golgi-fragmentation was found in a CPAF-deficient mutant. Surprisingly, sphingomyelin transport into the inclusion and into the bacteria, as measured by fluorescence accumulation upon addition of labelled ceramide, was not reduced during penicillin-treatment. Thus, both Golgi-fragmentation and transport of sphingomyelin to C. trachomatis still occurred in this model of persistence. The portion of cells in which CPAF was detected in the cytosol, either by immunofluorescence or by immune-electron microscopy, was drastically reduced in cells cultured in the presence of penicillin. These data argue against an essential role of cytosolic CPAF for Golgi-fragmentation or for sphingomyelin transport in chlamydial infection.
authors: Institute of Medical Microbiology and Hygiene, University Medical Centre Freiburg, Freiburg, Germany.
authors: Stephanie
authors: S
authors: Dille
authors: Institute of Medical Microbiology and Hygiene, University Medical Centre Freiburg, Freiburg, Germany.
authors: Katharina
authors: K
authors: Herbst
authors: Institute of Medical Microbiology and Hygiene, University Medical Centre Freiburg, Freiburg, Germany.
authors: Larisa
authors: L
authors: Volceanov
authors: Institute of Experimental and Clinical Pharmacology and Toxicology, University of Freiburg, Freiburg, Germany.
authors: Thilo
authors: T
authors: Nölke
authors: BIOSS Centre for Biological Signalling Studies, University of Freiburg, Freiburg, Germany.
authors: Oliver
authors: O
authors: Kretz
authors: Institute of Medical Microbiology and Hygiene, University Medical Centre Freiburg, Freiburg, Germany.
authors: Georg
authors: G
authors: Häcker
mesh_terms: D000818:Animals; D001426:Bacterial Proteins / Q000378:metabolism*; D001692:Biological Transport; D002460:Cell Line; D002478:Cells, Cultured; D002518:Ceramides / Q000378:metabolism; D002690:Chlamydia Infections / Q000382:microbiology; D002692:Chlamydia trachomatis / Q000187:drug effects* / Q000235:genetics / Q000378:metabolism*; D010450:Endopeptidases / Q000378:metabolism*; D006056:Golgi Apparatus / Q000378:metabolism*; D006367:HeLa Cells; D006801:Humans; D051379:Mice; D010406:Penicillins / Q000494:pharmacology*; D013109:Sphingomyelins / Q000378:metabolism*
chemical_list: D001426:Bacterial Proteins; D002518:Ceramides; D010406:Penicillins; D013109:Sphingomyelins; D010450:Endopeptidases