Hinse_2011_BMC.Genomics_12_400

BACKGROUND Streptococcus gallolyticus subsp gallolyticus is an important causative agent of infectious endocarditis while the pathogenicity of this species is widely unclear To gain insight into the pathomechanisms and the underlying genetic elements for lateral gene transfer we sequenced the entire genome of this pathogen RESULTS We sequenced the whole genome of S gallolyticus subsp gallolyticus strain ATCC BAA-2069 consisting of a 2,356,444 bp circular DNA molecule with a G+C-content of 37.65 and a novel 20,765 bp plasmid designated as pSGG1 Bioinformatic analysis predicted 2,309 ORFs and the presence of 80 tRNAs and 21 rRNAs in the chromosome Furthermore 21 ORFs were detected on the plasmid pSGG1 including tetracycline resistance genes telL and tet(O/W/32/O Screening of 41 S gallolyticus subsp gallolyticus isolates revealed one plasmid pSGG2 homologous to pSGG1 We further predicted 21 surface proteins containing the cell wall-sorting motif LPxTG which were shown to play a functional role in the adhesion of bacteria to host cells In addition we performed a whole genome comparison to the recently sequenced S gallolyticus subsp gallolyticus strain UCN34 revealing significant differences CONCLUSIONS The analysis of the whole genome sequence of S gallolyticus subsp gallolyticus promotes understanding of genetic factors concerning the pathogenesis and adhesion to ECM of this pathogen For the first time we detected the presence of the mobilizable pSGG1 plasmid which may play a functional role in lateral gene transfer and promote a selective advantage due to a tetracycline resistance.