Researchers sample hydrogenotrophic microbes in the healthy human colon
January 05, 2020
Sulfate-reducing bacteria (SRB) thrive in the presence of sulfate (a byproduct of eating foods such as meat, milk or eggs that have high levels of sulfur-containing amino acids).
The SRB generally outnumbered acetogens in the right colon, Carbonero said, while acetogens were more abundant than SRB in the left colon and rectum.
The researchers found variation among individual study subjects, particularly in the abundance of the three classes of microbes at different biopsy sites. And the team made a surprising discovery when analyzing biopsies taken less than a centimeter apart: microbial diversity can occur even at this small scale.
"These data indicate that if you get down to the scale at which these microbes make their living, perhaps it's not all the same," Gaskins said. "We haven't begun yet to think at that spatial scale."
The finding is relevant because disease tends to originate in very specific regions of the colon, Greenberg said. Ulcerative colitis starts at the rectum and then proceeds "upriver," he said. "When you see Crohn's disease you see an area of involvement, then it's normal and then you see another area of involvement. And if you do surgery and remove the disease, the disease almost always recurs from the point of removal because - we believe - it's been reseeded with microbes."
Future studies will examine the role of hydrogenotrophic microbes in constipation and will look at how diet affects the composition and abundance of microbes in the colon, the researchers said.
Source: University of Illinois at Urbana-Champaign