Key points:
- Researchers have identified the mechanism that has allowed for the longevity of a deadly strain of cholera bacteria.
- The bacteria employ a two-part defense system where a protein and an enzyme work together to destroy foreign plasmid DNA.
- These findings can inform future treatment development by offering new pathways for drugmakers to investigate.
The longevity of the deadly strain of cholera bacteria – Vibrio cholerae – has been a mystery. Now, a study, published in Nature, uncovers how this dangerous strain has managed to out-compete other pathogenic variants over decades.
Researchers used a combination of laboratory analysis and cryo-electron-microscope imaging to identify a unique defense system. V. cholerae utilize a two-part system to destroy plasmids and defend against parasitic mobile genetic elements. This strategy has protected and preserved the bacterial strain, contributing to its longevity.
As part of the two-part defense system, one protein targets plasmid DNA with remarkable accuracy. At the same time, a complementary enzyme shreds the plasmid DNA by unwinding its helix. Researchers likened this system to some of the CRISPR-Cascade complexes, which are based on bacterial immune systems.
“This unique defense system could be a target for treatment or prevention,” explained study author David Taylor, professor at The University of Texas at Austin. “If we can remove this defense, it could leave it vulnerable, or if we can turn its own immune system back on the bacteria, it would be an effective way to destroy it.”
The team hopes their findings can lead to a treatment breakthrough. There is a vaccine to fight cholera, but protection against symptoms drops after just three months. The findings of this study can inform treatment development by offering new pathways for drugmakers to investigate.