Colonization by the human
and animal parasite, Giardia, changed the species composition of the mouse
microbiome in a way that might be harmful.
"This shift is
generally characterized by more aerobic bacteria and less diversity of
anaerobic species in the gastrointestinal tract," said coauthor Scott C.
Dawson, Associate Professor of Microbiology and Molecular Genetics, the
University of California, Davis. "This suggests that Giardia infection
could -- at least in part -- be an ecological disease, with parasite
colonization disrupting the previously stable ecology of the gut."
Indeed, "We found
changes in the host microbial community throughout the entire gastrointestinal
tract," said Dawson. These findings challenge the conventional wisdom that
Giardia is a disease of the small intestine.
"We infected mice with
Giardia, sacrificed them at different times post-infection, and sequenced
specific regions throughout the entire gastrointestinal tract using
high-throughput 16S ribosomal RNA sequencing," said Dawson. This enabled
the investigators to quantify the shifts in microbial diversity in each part of
the GI tract, following infection. They also pre-treated one cohort of mice
with antibiotics, to determine if that pretreatment resulted in different
shifts in the microbiome as compared to those in mice not receiving antibiotics
(it did so).
See:
Posted by Dr. Tim Sandle