UNIQUE viruses called bacteriophages may play an important role in competition among bacterial strains, influencing the overall ecosystem of the human intestine, according to researchers at The University of Texas-Arlington and The University of Texas Southwestern Medical Center.
A team led by Lora V. Hooper, an associate professor of immunology and microbiology at the Southwestern Medical Center, and University of Texas-Arlington assistant professor of biology Jorge Rodrigues examined the bacteriophages, or phages, produced by genetic information harbored in the chromosome of the mammalian gut bacterium Enterococcus faecalis.
They found that a phage unique to E. faecalis strain V583 in mice acts as a predator, infecting and harming other similar, competing bacterial strains. They believe that these lab results suggest what goes on in the intestines of people.
"This organism is using phages as a way to compete in your gut. If the phage is released and gets rid of all the other microbes, then strain V583 will have more nutrients available," Rodrigues said. "It opens up new questions about the role of phages in the gut system. Ultimately, you could use this as a technique to control bacteria in a natural way."
The findings were presented in October in Proceedings of the National Academy of Sciences in a paper called "A Composite Bacteriophage Alters Colonization by an Intestinal Commensal Bacterium," which is available at www.pnas.org/content/early/2012/10/04/1206136109.
"Now that we've established the role of these bacteriophages, our team is working on trying to discover the specific triggers that lead to phage production in the gut," Hooper said. "We also want to understand whether there are other phages that play a role in shaping the composition of gut bacterial communities."