However, recent researches have shown that this bacterium can use other invasion pathways mediating either Trigger or Zipper entry processes. Following eukaryotic cell invasion, Salmonella has to ensure its survival and proliferation within host cells. To do so, this bacterium resides either within a membrane-bound vacuole or freely within

host cell cytosol. It is Y-27632 supplier not clear why Salmonella has developed these alternate mechanisms for cell invasion and proliferation, but this provides a new insight into the mechanisms leading to Salmonella-induced diseases. Thus, the aim of this review is to show the evolution of Salmonella–host cell interaction paradigms by summarizing the different strategies used by Salmonella

serotypes to invade and proliferate into eukaryotic cells. “
“The physiology of the response in the methanotrophic bacterium Methylococcus capsulatus Bath towards thermal and solvent stress was studied. A systematic investigation of the toxic effects of organic compounds (chlorinated phenols and alkanols) on the growth of this bacterium was carried out. The sensitivity to the tested alkanols correlated with their chain length and hydrophobicity; methanol was shown to be an exception to which the cells showed a very high tolerance. This can be explained by the adaptation of these bacteria to growth on C1 compounds. On the other hand, selleck inhibitor M. capsulatus Bath was very sensitive towards the tested chlorinated phenols. The high toxic effect of phenolic compounds on methanotrophic bacteria might be explained by the occurrence of toxic reactive oxygen species. In addition, a physiological proof of the presence of cis–trans isomerization

as a membrane-adaptive response mechanism in M. capsulatus isothipendyl was provided. This is the first report on physiological evidence for the presence of the unique postsynthetic membrane-adaptive response mechanism of the cis–trans isomerization of unsaturated fatty acids in a bacterium that does not belong to the genera Pseudomonas and Vibrio where this mechanism was already reported and described extensively. Since the early 1990s, the isomerization of cis–trans unsaturated fatty acids as a unique mechanism known to enable bacteria of the genera Pseudomonas and Vibrio to adapt to several forms of environmental stress was already investigated intensely (Okuyama et al., 1991; Heipieper et al., 1992). The extent of isomerization apparently correlates with the fluidity effects caused by an increase in temperature or the accumulation of membrane-toxic organic compounds. The cis–trans isomerase (Cti) activity is constitutively present and is located in the periplasm; it does not require ATP or any other cofactor, and it operates in the absence of de novo synthesis of lipids (Heipieper et al., 2003).