417: Bacteriophage Blocks Bacterial Bouncers

This episode: A phage defends its genome against bacterial host
defenses by building a wall to keep them out!


Download Episode (7.0 MB, 10.2 minutes)

Show notes:
Microbe of the episode: Myroides odoratus and M.
odoratimimus

News item

Takeaways
Parasites and their hosts are constantly in arms races with each
other, each thriving best when it acquires new and more effective
methods of attack, defenses, defenses against defenses, and so
on. Bacterial defenses against viruses that infect them mostly
involve cutting up viral genomes, either by the indiscriminate
specific-cutting restriction enzymes, or by adaptive,
sequence-sensing CRISPR/Cas systems.

Bacteriophages have proteins that can defend against the
CRISPR/Cas system, but they mostly require the sacrifice of
multiple failed infections before the proteins build up enough to
defeat the defense. In this study, a phage is discovered that can
immediately defend against all DNA-cutting systems, by
constructing a nucleus-like protective compartment inside the
host.

Journal Paper:
Mendoza SD, Nieweglowska ES, Govindarajan S, Leon LM, Berry JD,
Tiwari A, Chaikeeratisak V, Pogliano J, Agard DA, Bondy-Denomy J.
2020. A bacteriophage nucleus-like compartment shields DNA from
CRISPR nucleases. Nature 577:244–248.


Other interesting stories:



Helpful vaginal microbes inhibit HIV infection (paper)

Engineering bacteria to fix nitrogen that grain plants can
use (paper)




 


Email questions or comments to bacteriofiles at gmail dot
com. Thanks for listening!


Subscribe: Apple Podcasts, Google Podcasts, Android, or RSS.
Support the show at Patreon, or check out the show
at Twitter or Facebook.