Our findings correlate with the fact that intracellular upregulation of ahpC and dps expression may be an important defense for survival against
phagocytic cells of the immune system. Although oxidative killing mechanisms of the phagocytic cells may contribute to B. fragilis oxidative stress response in vivo, the current study cannot rule out that other intracellular environmental conditions may also affect the expression of ahpC and dps. One such factor is the depletion BIBW2992 purchase of iron availability in the phagolysosome compartment. Induction of ahpC and dps expression is also affected by iron limitation in vitro (data not shown), which could account for additional regulation of B. fragilis genes following internalization by phagocytic cells. In conclusion, these results indicate that the FbFPs are suitable to be used as transcriptional fusion reporters in obligate anaerobic bacteria. There seems to be a significant potential for FbFPs in the analysis of gene expression in vivo in anaerobic environments such as the human colon as well as in extraintestinal infections when used in combination with modern in vivo imaging techniques. This work learn more was supported in part by NIH/NIAID research grants AI068659 and AI079183 to E.R.R. and grant AI40588 to C.J.S. The authors
are grateful to T. Whitehead for helpful discussions. “
“The recent boom in phage therapy and phage biocontrol requires the design of suitable cocktails of genetically different bacteriophages. The current methods for typing phages need significant quantities of purified DNA, may require a priori genetic information and are cost and time consuming. We have evaluated the randomly amplified polymorphic DNA (RAPD)-PCR technique to produce unique and reproducible band patterns from 26 different bacteriophages infecting Staphylococcus
epidermidis, Staphylococcus aureus, Lactococcus lactis, Escherichia coli, Streptococcus thermophilus, Bacillus subtilis and Lactobacillus casei bacterial strains. Initially, purified DNA and phage suspensions of seven selected Casein kinase 1 phages were used as a template. The conditions that were found to be optimal 8 μM of 10-mer primers, 3 μM magnesium oxalacetate and 5% dimethyl sulfoxide. The RAPD genomic fingerprints using a phage titer suspension higher than 109 PFU mL−1 were highly reproducible. Clustering by the Pearson correlation coefficient and the unweighted pair group method with arithmetic averages clustering algorithm correlated largely with genetically different phages infecting the same bacterial species, although closely related phages with a similar DNA restriction pattern were indistinguishable. The results support the use of RAPD-PCR for quick typing of phage isolates and preliminary assessment of their genetic diversity bypassing tedious DNA purification protocols and previous knowledge of their sequence.
Related posts:
- To date no other bacteriophage morpho sorts are already observed
- An aggre gate of about 70% of T4 ORFs are conserved in at least a
- However, their efficiency measured in vitro did not correlate wit
- In this context Bcl two, CDK, as well as other possible intracellular targets ca
- It is difficult to correlate in vitro toxin concentration with in