28 research outputs found
A Dominant-Negative Approach That Prevents Diphthamide Formation Confers Resistance to Pseudomonas Exotoxin A and Diphtheria Toxin
Diphtheria toxin (DT), Pseudomonas aeruginosa Exotoxin A (ETA) and cholix toxin from Vibrio cholerae share the same mechanism of toxicity; these enzymes ADP-rybosylate elongation factor-2 (EF-2) on a modified histidine residue called diphthamide, leading to a block in protein synthesis. Mutant Chinese hamster ovary cells that are defective in the formation of diphthamide have no distinct phenotype except their resistance to DT and ETA. These observations led us to predict that a strategy that prevents the formation of diphthamide to confer DT and ETA resistance is likely to be safe. It is well documented that Dph1 and Dph2 are involved in the first biochemical step of diphthamide formation and that these two proteins interact with each other. We hypothesized that we could block diphthamide formation with a dominant negative mutant of either Dph1 or Dph2. We report in this study the first cellular-targeted strategy that protects against DT and ETA toxicity. We have generated Dph2(C-), a dominant-negative mutant of Dph2, that could block very efficiently the formation of diphthamide. Cells expressing Dph2(C-) were 1000-fold more resistant to DT than parental cells, and a similar protection against Pseudomonas exotoxin A was also obtained. The targeting of a cellular component with this approach should have a reduced risk of generating resistance as it is commonly seen with antibiotic treatments
Race and Gender Differences in Respiratory Illness Prevalence and Their Relationship to Environmental Exposures in Children 7 to 14 Years of Age
Recommended from our members
A practical perspective on the potential of rechargeable Mg batteries
Acknowledgements: This work was funded by European Union's Horizon 2020 research and innovation program under the FET Proactive call with grant agreement no 824066 via the “E-MAGIC” project.Emerging energy storage systems based on abundant and cost-effective materials are key to overcome the global energy and climate crisis of the 21st century.</jats:p
Reduction in SBPase Activity by Antisense RNA in Transgenic Rice Plants: Effect on Photosynthesis, Growth, and Biomass Allocation at Different Nitrogen Levels
S100A4-induced cell motility and metastasis is restricted by the Wnt/β-catenin pathway inhibitor calcimycin in colon cancer cells
Calcimycin restricts Wnt/β-catenin–regulated S100A4 expression, leading to reduced S100A4-mediated cell migration and invasion in colon cancer cells, as well as to inhibition of metastasis formation in xenografted mice