Bacteria may lack a true immune system, but this does not leave them defenseless against bacteriophage viruses and other pathogens. A system of genomic sequence elements called clustered regularly interspaced short palindromic repeats (CRISPR) and various CRISPR-associated proteins (Cas) help to recognize and destroy foreign genetic material delivered by such invaders.
An international research group led by Akeo Shinkai from the RIKEN SPring-8 Center and John van der Oost of Wageningen University in the Netherlands has now dissected one such CRISPR-Cas pathway, revealing functional insights that also highlight important differences in how these systems operate across bacterial species.
The researchers focused their attention on Thermus thermophilus, a bacterium that thrives at high temperatures and features a relatively simple and compact genome, making it amenable to experimental work. Of the bacterium's multiple CRISPR-Cas pathways, the researchers explored the pathway known as subtype III-B, which targets foreign RNA rather than DNA.
Click "source" to read more.