SFB796 - Sub project B5
(sub project concluded on Dec 31 2012)

Suche


Analysis of virulence factors of Corynebacterium diphtheriae

 

Project summary

In frame of sub-project B5, interactions of pathogenic bacterium Corynebacterium diphtheriae with human host cells are investigated. In the previous funding period we could demonstrate that the DIP1281 protein is crucial for adhesion to the host and invasion into host cells. Furthermore, we were able to show that pili are - although important for host cell recognition and attachment - not exclusively determining adhesion rate. In fact, also a pilus-free strain investigated by us showed strong attachment to epithelial cells. High numbers of extended pili even seems to be counterproductive to invasion. While adhesion did not result in a signaling response by reporter host cell lines, we could show that the NFκB pathway is activated as a result of C. diphtheriae internalization.

Based on the results obtained in the previous funding period, we will concentrate on the internalization process of the bacteria and the establishment of C. diphtheriae within the host in three different subprojects. In subproject 1 we will use a Caenorhabtitis elegans worm model established by us to characterize new virulence factors. In subproject 2, the survival of C. diphtheriae in macrophages will be investigated and compared to the behavior of related species Corynebacterium glutamicum, Corynebacterium pseudotuberculosis and Corynebacterium ulcerans using mainly a combination of molecular biology-based approaches and fluorescence microscopy. Subproject 3 will concentrate on bacterial effectors, which are (i) manipulating the internalization machinery of the cell and (ii) interact with signaling pathways of host cells.

 



In situ-Immunofluorescence staining of C. diphtheriae wild type strain ISS3319 after 4h of infection of Detroit562 monolayers (overlay); differential staining: extracellular bacteria in orange, intracellular bacteria in red and the Detroit562 cells in blue.

 

Project relevant publications

  • Sangal, V., Tucker, N. P., Burkovski, A. & Hoskisson, P. A. (2012).   The draft genome sequence of Corynebacterium diphtheriae mitis NCTC 3529 reveals significant diversity between the primary disease causing biovars.   J. Bacteriol.,  DOI: 10.1128/JB.00503-12 .

  • Rheinlaender, J., Gräbner, A., Ott, L., Burkovski, A. & Schäffer, T. E. (2012).   Nanoscale analyses of Corynebacterium diphtheriae pili by atomic force microscopy.   Eur. Biophys. J.,  DOI: 10.1007/s00249-012-0818-4 .

  • Ott, L., McKenzie, A., Baltazar, A. T., Britting, S., Bischof, A., Burkovski, A. & Hoskisson, P. A. (2012).   Evaluation of invertebrate infection models for pathogenic corynebacteria.   FEMS Immunol. Med. Microbiol.,  DOI: 10.1111/j.1574-695X.201 .

  • Trost, E., Al-Dilaimi, A., Papavasiliou, P., Schneider, J., Viehoever, P., Burkovski, A., Soares, S. C., Almeida, S. S., Dorella, F. A., Miyoshi, A., Azevedo, V., Schneider, M. P., Silva, A., Santos, C. S., Santos, L. S., Sabbadini, P., Dias, A. A., Hirata, R. Jr., Mattos-Guaraldi, A. L. & Tauch A. (2011).   Comparative analysis of two complete Corynebacterium ulcerans genomes and detection of candidate virulence factors.   BMC Genomics 12, 383.

  • Poetsch, A., Haußmann, U. & Burkovski, A. (2011).   Proteomics of corynebacteria: From biotechnology workhorses to pathogens.   Proteomics 11, 3244 - 3255.

  • Trost, E., Ott, L., Schneider, J. Schröder, J., Jaenicke, S., Goesmann, A., Husemann, P., Stoye, J., Alves Dorella, F., Souza Rocha, F., de Castro Soares, S., D'Afonseca, V., Azevedo, V., Burkovski, A., Guiso, N. & Tauch, A. (2010).   The complete genome sequence of Corynebacterium pseudotuberculosis FRC41 isolated from a 12-year-old girl with necrotizing lymphadenitis revealed insights into gene-regulatory networks contributing to virulence.   BMC Genomics 11, 728.

  • Ott, L., Höller, M., Rheinlaender, J., Schäffer, T. E., Hensel & Burkovski, A. (2010).   Strain-specific differences in pili formation and the interaction of Corynebacterium diphtheriae with host cells.   BMC Microbiol. 10, 257.

  • Ott, L., Höller, M., Gerlach, R. G., Hensel, M., Rheinlaender, J., Schäffer, T. E. & Burkovski, A. (2010).   Corynebacterium diphtheriae invasion-associated protein (DIP1281) is involved in cell surface organization, adhesion and internalization in epithelial cells.   BMC Microbiol. 10, 2.

  • Amon, J., Lüdke, A., Titgemeyer, F. & Burkovski, A. (2008).   General and regulatory proteolysis in corynebacteria.   Corynebacteria: genomics and molecular biology, 295-311.