monocytogenes to β-lactams Selleckchem Gefitinib was examined. Deletion mutant in lmo1941 was constructed and subjected to studies, which revealed that the deletion of lmo1941 had no effect on susceptibility and tolerance to penicillin G and ampicillin but resulted, however, in increased susceptibility of L. monocytogenes to several cephalosporins. Subsequently, the potential effect of lmo1941 mutation on the cell wall of L. monocytogenes was investigated. The analysis revealed quantitative changes in the muropeptide profile of peptidoglycan and a decrease in density of the high-density zone of cell wall of the mutant strain. Both these changes were observed in cells taken from the stationary phase. These results indicate that the surface protein
Lmo1941 affects peptidoglycan composition and cell wall structure of L. monocytogenes in the stationary phase of growth. “
“The genus Rickettsiella comprises intracellular bacterial pathogens of a wide range of arthropods
that are currently classified in four recognized species and numerous further pathotypes. However, both the delineation of and the synonymization of pathotypes with species TSA HDAC price are highly problematic. In the sequel of a previous phylogenomic study at the supra-generic level, nine selected genes – the 16S and 23S rRNA genes and the protein-encoding genes dnaG, ftsY, gidA, ksgA, rpoB, rpsA, and sucB – were evaluated for their potential as markers for the generic and infra-generic taxonomic classification of Rickettsiella-like bacteria. A methodological approach combining phylogenetic reconstruction with likelihood-based significance however testing was employed on the basis of sequence data from the species Rickettsiella grylli and Rickettsiella popilliae, pathotypes ‘Rickettsiella melolonthae’ and ‘Rickettsiella tipulae’. This study provides the first multilocus sequence typing (MLST) data for the genus Rickettsiella and identifies two new genetic markers, gidA and sucB, for the infra-generic classification within this taxon. In particular, aforesaid genes were found more reliable
and informative markers than the corresponding 16S rRNA-encoding sequences that failed to produce strictly significant infra-generic taxonomic assignments. However, gidA- and sucB-based phylogenies were consistent with the currently accepted view of species delineation and species-pathotype synonymization within the genus Rickettsiella. The genus Rickettsiella (Philip) comprises intracellular bacterial pathogens of a wide range of arthropods. The currently valid taxonomy of these bacteria (Garrity et al., 2005) is primarily based on the indication of a strain’s original host. Moreover, the resulting pathotype designation is partially superposed by the morpho- and serologically founded distinction of four recognized species, namely the nomenclatural type species Rickettsiella popilliae (Dutky & Gooden), Rickettsiella grylli (Vago & Martoja), Rickettsiella chironomi (Weiser), and Rickettsiella stethorae (Hall & Badgley).