Construction of a Francisella tularensis two-dimensional electrophoresis protein database

We have started the construction of a two-dimensional database of the prote ome of Francisella tularensis, a bacterium that is responsible for the high ly pathogenic disease tularemia. The genome of this intracellular pathogen is not completely sequenced yet and, currently, information about only 66 p roteins is available from NCBI database. We have analyzed the F: tularensis live vaccine strain by two-dimensional gel electrophoresis with immobilize d pH 3-10 gradient in the first dimension and 9-16% gradient or tricine SDS -PAGE in the second dimension. In both cases about 2000 spots were detected . Furthermore, we compared the protein pattern of the nonvirulent F: tulare nsis live vaccine strain with protein profiles of two wild type clinical is olates and more than 50 differentially expressed proteins were counted. The separated proteins are going to be identified by peptide mass fingerprinti ng. However, due to the lack of complete genome sequence data only eight pr oteins were unambiguously identified. Among them, acid phosphatase and the most basic isoform of a hypothetical 23 kDa protein are characteristic only for virulent strains.