433: Probiotic Promotes Pathogen Peacefulness

This episode: A probiotic can protect intestine-like cell growths
from destruction by pathogens, but it can also be infected by a
virus that makes it more harmful to intestinal cells!


Download Episode (6.9 MB, 10.1 minutes)

Show notes:
Microbe of the episode: Euphorbia yellow mosaic virus


 


News item


Takeaways


There are many strains of Escherichia coli. Some are
pathogenic, in the gut or the urinary tract, and a subset
of those are very dangerous, such as the enterohemorrhagic
O157:H7 strain. Many others are commensals, living
peacefully as part of our gut community. And some strains
can be beneficial to the host, protecting from and reducing
the severity of disease. One such strain is called E.
coli Nissle.


 


This study used an advanced model of human intestines
called organoids, where stem cells are induced to develop
into hollow spheres of intestinal epithelium in which all
cell types of a normal intestinal wall are
represented. E. coli pathogens typically destroy
these organoids and escape from inside, but Nissle was able
to prevent this destruction and enable coexistence between
the pathogen and the host cells. Nissle suffered for this
protection though; O157:H7 carries a toxin-encoding phage
that can infect and kill susceptible E.
coli strains. Those Nissle cells that survived this
infection could resist the phage, but were not as
beneficial to the organoids due to the toxin they now
produced.


Journal Paper:
Pradhan S, Weiss AA. 2020. Probiotic Properties of Escherichia
coli Nissle in Human Intestinal Organoids. mBio
11(4):e01470-20.



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Photosynthetic microbes engineered to produce spider silk




 


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


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