1887

Abstract

To colonize and cause infection in the host, pathogens must be well equipped to respond to and survive in several hostile conditions. TolC, an outer membrane channel component used by multidrug efflux pumps and type I secretion systems, is considered to be largely involved in bacterial physiology and virulence. In this study, we attempted to investigate the possible roles of TolC2, a homologue of TolC, in the pathogenesis of .

The cell viability was investigated under stress conditions (oxidative, thermal, acid and osmotic). Virulence was assessed by lethal intraperitoneal injection of mice. The underlying mechanisms of the attenuation were further explored by serum bactericidal, phagocytosis and organ burden assays.

The deletion of caused increased sensitivity to oxidative, thermal and acid challenges, indicating a critical role of TolC2 in survival under stress conditions. The intraperitoneal injection of mice showed that the Δ mutant caused significantly decreased mortality, suggesting the involvement of TolC2 in the virulence of . In the serum-killing assays, the Δ mutant showed significantly reduced survival ability when exposed to fresh serum. By the phagocytosis assays, we found that the loss of rendered the mutant susceptible to phagocytosis by macrophages. Finally, the organ burden assays revealed decreased colonization of Δ in lungs, indicating a higher bacterial clearance rate in mice in the absence of TolC2.

Our findings demonstrate that TolC2 contributes to the virulence of by helping survival and maximal colonization in the host.

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2017-08-01
2024-04-19
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References

  1. Chiers K, De Waele T, Pasmans F, Ducatelle R, Haesebrouck F. Virulence factors of Actinobacillus pleuropneumoniae involved in colonization, persistence and induction of lesions in its porcine host. Vet Res 2010; 41:65 [View Article][PubMed]
    [Google Scholar]
  2. Bossé JT, Janson H, Sheehan BJ, Beddek AJ, Rycroft AN et al. Actinobacillus pleuropneumoniae: pathobiology and pathogenesis of infection. Microbes Infect 2002; 4:225–235 [View Article][PubMed]
    [Google Scholar]
  3. Koronakis V, Eswaran J, Hughes C. Structure and function of TolC: the bacterial exit duct for proteins and drugs. Annu Rev Biochem 2004; 73:467–489 [View Article][PubMed]
    [Google Scholar]
  4. Tseng TT, Tyler BM, Setubal JC. Protein secretion systems in bacterial-host associations, and their description in the Gene Ontology. BMC Microbiol 2009; 9:S2 [View Article][PubMed]
    [Google Scholar]
  5. Kamal N, Shafer WM. Biologic activities of the TolC-like protein of Neisseria meningitidis as assessed by functional complementation in Escherichia coli. Antimicrob Agents Chemother 2010; 54:506–508 [View Article][PubMed]
    [Google Scholar]
  6. Bina XR, Provenzano D, Nguyen N, Bina JE. Vibrio cholerae RND family efflux systems are required for antimicrobial resistance, optimal virulence factor production, and colonization of the infant mouse small intestine. Infect Immun 2008; 76:3595–3605 [View Article][PubMed]
    [Google Scholar]
  7. Posadas DM, Martín FA, Sabio Y García JV, Spera JM, Delpino MV et al. The TolC homologue of Brucella suis is involved in resistance to antimicrobial compounds and virulence. Infect Immun 2007; 75:379–389 [View Article][PubMed]
    [Google Scholar]
  8. Hahn A, Stevanovic M, Mirus O, Schleiff E. The TolC-like protein HgdD of the Cyanobacterium anabaena sp. PCC 7120 is involved in secondary metabolite export and antibiotic resistance. J Biol Chem 2012; 287:41126–41138 [View Article][PubMed]
    [Google Scholar]
  9. Zgurskaya HI, Krishnamoorthy G, Ntreh A, Lu S. Mechanism and function of the outer membrane channel TolC in multidrug resistance and physiology of enterobacteria. Front Microbiol 2011; 2:189 [View Article][PubMed]
    [Google Scholar]
  10. Ferhat M, Atlan D, Vianney A, Lazzaroni JC, Doublet P et al. The TolC protein of Legionella pneumophila plays a major role in multi-drug resistance and the early steps of host invasion. PLoS One 2009; 4:e7732 [View Article][PubMed]
    [Google Scholar]
  11. Platz GJ, Bublitz DC, Mena P, Benach JL, Furie MB et al. A tolC mutant of Francisella tularensis is hypercytotoxic compared to the wild type and elicits increased proinflammatory responses from host cells. Infect Immun 2010; 78:1022–1031 [View Article][PubMed]
    [Google Scholar]
  12. Buckley AM, Webber MA, Cooles S, Randall LP, La Ragione RM et al. The AcrAB-TolC efflux system of Salmonella enterica serovar Typhimurium plays a role in pathogenesis. Cell Microbiol 2006; 8:847–856 [View Article][PubMed]
    [Google Scholar]
  13. Li Y, Cao S, Zhang L, Lau GW, Wen Y et al. A TolC-like protein of Actinobacillus pleuropneumoniae is involved in antibiotic resistance and biofilm formation. Front Microbiol 2016; 7: [View Article][PubMed]
    [Google Scholar]
  14. Xie F, Zhang Y, Li G, Zhou L, Liu S et al. The ClpP protease is required for the stress tolerance and biofilm formation in Actinobacillus pleuropneumoniae. PLoS One 2013; 8:e53600 [View Article][PubMed]
    [Google Scholar]
  15. Deininger KN, Horikawa A, Kitko RD, Tatsumi R, Rosner JL et al. A requirement of TolC and MDR efflux pumps for acid adaptation and GadAB induction in Escherichia coli. PLoS One 2011; 6:e18960 [View Article][PubMed]
    [Google Scholar]
  16. Zhang L, Li Y, Wen Y, Lau GW, Huang X et al. HtrA is important for stress resistance and virulence in Haemophilus parasuis. Infect Immun 2016; 84:2209–2219 [View Article][PubMed]
    [Google Scholar]
  17. Lone AG, Deslandes V, Nash JH, Jacques M, Macinnes JI. malT knockout mutation invokes a stringent type gene-expression profile in Actinobacillus pleuropneumoniae in bronchoalveolar fluid. BMC Microbiol 2009; 9:195 [View Article][PubMed]
    [Google Scholar]
  18. Tan RM, Kuang Z, Hao Y, Lee F, Lee T et al. Type IV pilus glycosylation mediates resistance of Pseudomonas aeruginosa to opsonic activities of the pulmonary surfactant protein A. Infect Immun 2015; 83:1339–1346 [View Article][PubMed]
    [Google Scholar]
  19. Imlay JA. The molecular mechanisms and physiological consequences of oxidative stress: lessons from a model bacterium. Nat Rev Microbiol 2013; 11:443–454 [View Article][PubMed]
    [Google Scholar]
  20. Thomas S, Holland IB, Schmitt L. The type 1 secretion pathway - the hemolysin system and beyond. Biochim Biophys Acta 2014; 1843:1629–1641 [View Article][PubMed]
    [Google Scholar]
  21. Linhartová I, Bumba L, Mašín J, Basler M, Osička R et al. RTX proteins: a highly diverse family secreted by a common mechanism. FEMS Microbiol Rev 2010; 34:1076–1112 [View Article][PubMed]
    [Google Scholar]
  22. Doyle CR, Pan JA, Mena P, Zong WX, Thanassi DG. TolC-dependent modulation of host cell death by the Francisella tularensis live vaccine strain. Infect Immun 2014; 82:2068–2078 [View Article][PubMed]
    [Google Scholar]
  23. Lindemann SR, Peng K, Long ME, Hunt JR, Apicella MA et al. Francisella tularensis Schu S4 O-antigen and capsule biosynthesis gene mutants induce early cell death in human macrophages. Infect Immun 2011; 79:581–594 [View Article][PubMed]
    [Google Scholar]
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