Insertional mutagenesis in the zoonotic pathogen Chlamydia caviae

Autoři: Kimberly Filcek aff001;  Katarina Vielfort aff002;  Samada Muraleedharan aff002;  Johan Henriksson aff002;  Raphael H. Valdivia aff003;  Patrik M. Bavoil aff001;  Barbara S. Sixt aff002
Působiště autorů: Department of Microbial Pathogenesis, University of Maryland, School of Dentistry, Baltimore, MD, United States of America aff001;  Laboratory for Molecular Infection Medicine Sweden (MIMS), Umeå Centre for Microbial Research, Department of Molecular Biology, Umeå University, Umeå, Sweden aff002;  Department of Molecular Genetics and Microbiology, Duke University, Durham, NC, United States of America aff003
Vyšlo v časopise: PLoS ONE 14(11)
Kategorie: Research Article
doi: 10.1371/journal.pone.0224324


The ability to introduce targeted genetic modifications in microbial genomes has revolutionized our ability to study the role and mode of action of individual bacterial virulence factors. Although the fastidious lifestyle of obligate intracellular bacterial pathogens poses a technical challenge to such manipulations, the last decade has produced significant advances in our ability to conduct molecular genetic analysis in Chlamydia trachomatis, a major bacterial agent of infertility and blindness. Similar approaches have not been established for the closely related veterinary Chlamydia spp., which cause significant economic damage, as well as rare but potentially life-threatening infections in humans. Here we demonstrate the feasibility of conducting site-specific mutagenesis for disrupting virulence genes in C. caviae, an agent of guinea pig inclusion conjunctivitis that was recently identified as a zoonotic agent in cases of severe community-acquired pneumonia. Using this approach, we generated C. caviae mutants deficient for the secreted effector proteins IncA and SinC. We demonstrate that C. caviae IncA plays a role in mediating fusion of the bacteria-containing vacuoles inhabited by C. caviae. Moreover, using a chicken embryo infection model, we provide first evidence for a role of SinC in C. caviae virulence in vivo.

Klíčová slova:

Animal models of infection – HeLa cells – Chicken models – Chlamydia – Chlamydia infection – Introns – Vero cells


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2019 Číslo 11