Title Talk: Proteomics and immunoproteomics of Gram-positive Bacteria in host-pathogen interactions
Frank Schmidt started his scientific career at the Max-Planck-Institute for Infectionbiology in Berlin. To date he is a Group Leader at the Medical University Greifswald, where his group investigates mechanisms of Gram-positive pathogens to discover potential targets for vaccination. In the past 17 years he gained a deep knowledge in proteomics and immunoproteomics and its application in the characterization of the pathophysiology of bacteria during infection. He also developed many FACS and proteomics related methods to understand host-pathogen interactions. Beside identification and quantitation of cytosolic proteins he also investigated the virulent potential of membrane associated or secreted proteins which act as the antagonist to the human immune system. Dr. Schmidt is co-chair of Infectious Disease Initiative of HUPO, editor for several proteome or microbiology related Journals and a guest professor in Austria.
S. aureus related diseases range from mild to severe infections. In general, proteome analysis approaches using data dependent acquisition (DDA) are known to provide lower reproducibility and comprehensiveness when compared to data-independent acquisition (DIA). In this study, a DIA spectral library was generated and benchmarked with a well characterized biological standard and used for the analysis of S. aureus interacting with S9 and murine cells. Protein analysis revealed up-regulations in oxidative stress, cell wall assembling and down-regulations in dNTP synthesis or biosynthetic activity. DIA analysis allowed a deep insight in the pathogen-host adaption and revealed many infection specific proteins which we further overexpressed as recombinant proteins to investigate the antibody response of S. aureus carrier or non-carrier or of patients suffering on sepsis. We further profiled their blood proteomes by DIA in order to find new candidates for diagnosis and prognosis.
Key Words: S. aureus, DIA, in vivo, proteomics, immunoproteomics
Correspondence: Dr. Dipl.-Ing. Frank Schmidt, EMA University Medicine Greifswald, Department of Functional Genomics, ZIK-FunGene Group Applied Proteomics, Friedrich-Ludwig-Jahnstr. 15a, D-17487 Greifswald, Germany