subtilis in our query), the zurA locus (similarity to ycdI in B. subtilis, mreA in S. aureus, and znuC in E. coli in our query), lmo0153 (similarity to ycdH in B. subtilis and znuA in E. coli in our query), lmo1671 (similarity to ycdH in B. subtilis and znuA in E. coli in our query),
and lmo1849 (similarity to ycdI in B. subtilis, mreA in S. aureus, and znuC in E. coli in our query). Quantitative RT-PCR analysis confirmed that zurR, lmo0153, and lmo1671 were up-regulated greater than 2-fold in a ΔzurR background (Fig. 4b). In particular, lmo0153 (similar to high-affinity zinc transporter) and lmo1671 (encoding a putative ABC transporter) both contain close matches to the B. subtilis Zur box consensus Selleckchem PD0325901 sequence and will make interesting loci for further study. In conclusion, we have created a precise selleck chemicals llc deletion of the gene encoding the regulator ZurR in L. monocytogenes. Virulence assays in mice demonstrate a subtle but statistically significant impact of the mutation upon virulence
potential. The mutation also influences cell size, motility, and resistance to toxic levels of zinc. Furthermore, we identified putative zinc uptake systems the expression of which is influenced by ZurR. Future work will be required to analyze the individual roles of these transporters in zinc transport in this important Wilson disease protein human pathogen. G.D. was funded by Science Foundation Ireland under the Research Frontiers Programme (05/RFP/Gen0021). The authors also wish to acknowledge the continued financial assistance of the Alimentary Pharmabiotic Centre (APC), funded by Science Foundation Ireland (SFI). We thank Suzanne Crotty for facilitating the electron microscopy work. “
“Campylobacter species are the most common cause of
bacterial gastroenteritis, with C. jejuni responsible for the majority of these cases. Although it is clear that livestock, and particularly poultry, are the most common source, it is likely that the natural environment (soil and water) plays a key role in transmission, either directly to humans or indirectly via farm animals. It has been shown using multilocus sequence typing that some clonal complexes (such as ST-45) are more frequently isolated from environmental sources such as water, suggesting that strains vary in their ability to survive in the environment. Although C. jejuni are fastidious microaerophiles generally unable to grow in atmospheric levels of oxygen, C. jejuni can adapt to survival in the environment, exhibiting aerotolerance and starvation survival. Biofilm formation, the viable but nonculturable state, and interactions with other microorganisms can all contribute to survival outside the host.