RRC ID 48520
著者 Sana TG, Flaugnatti N, Lugo KA, Lam LH, Jacobson A, Baylot V, Durand E, Journet L, Cascales E, Monack DM.
タイトル Salmonella Typhimurium utilizes a T6SS-mediated antibacterial weapon to establish in the host gut.
ジャーナル Proc Natl Acad Sci U S A
Abstract The mammalian gastrointestinal tract is colonized by a high-density polymicrobial community where bacteria compete for niches and resources. One key competition strategy includes cell contact-dependent mechanisms of interbacterial antagonism, such as the type VI secretion system (T6SS), a multiprotein needle-like apparatus that injects effector proteins into prokaryotic and/or eukaryotic target cells. However, the contribution of T6SS antibacterial activity during pathogen invasion of the gut has not been demonstrated. We report that successful establishment in the gut by the enteropathogenic bacterium Salmonella enterica serovar Typhimurium requires a T6SS encoded within Salmonella pathogenicity island-6 (SPI-6). In an in vitro setting, we demonstrate that bile salts increase SPI-6 antibacterial activity and that S Typhimurium kills commensal bacteria in a T6SS-dependent manner. Furthermore, we provide evidence that one of the two T6SS nanotube subunits, Hcp1, is required for killing Klebsiella oxytoca in vitro and that this activity is mediated by the specific interaction of Hcp1 with the antibacterial amidase Tae4. Finally, we show that K. oxytoca is killed in the host gut in an Hcp1-dependent manner and that the T6SS antibacterial activity is essential for Salmonella to establish infection within the host gut. Our findings provide an example of pathogen T6SS-dependent killing of commensal bacteria as a mechanism to successfully colonize the host gut.
巻・号 113(34)
ページ E5044-51
公開日 2016-8-23
DOI 10.1073/pnas.1608858113
PII 1608858113
PMID 27503894
PMC PMC5003274
MeSH Animals Antibiosis* Bacterial Proteins / biosynthesis Bacterial Proteins / genetics Bacterial Proteins / toxicity* Bile Acids and Salts / pharmacology Culture Media / chemistry Female Gastrointestinal Microbiome / drug effects Gastrointestinal Tract / microbiology Gastrointestinal Tract / pathology Genomic Islands Klebsiella oxytoca / drug effects Klebsiella oxytoca / growth & development Male Mice Mice, Inbred C57BL Salmonella Infections, Animal / microbiology* Salmonella Infections, Animal / pathology Salmonella typhimurium / genetics Salmonella typhimurium / growth & development Salmonella typhimurium / pathogenicity* Type VI Secretion Systems / genetics* Type VI Secretion Systems / metabolism Virulence Factors / biosynthesis Virulence Factors / genetics Virulence Factors / toxicity*
IF 9.412
引用数 105
WOS 分野 MICROBIOLOGY
リソース情報
一般微生物 JCM 13464