Experts may soon be able to stock your gut with beneficial bacteria After discovering how a common virus infects and controls bacteria in the gut, experts are closer to finding ways to manipulate the composition of the gut microbiome – which has a major influence on human health. The research, led by Rutgers University, may ultimately lead to the creation of beneficial bacteria that produce medicines and clean up pollutants.
Study co-author Konstantin Severinov is a principal investigator at the Waksman Institute of Microbiology and a professor of Molecular Biology and Biochemistry in the School of Arts and Sciences at Rutgers University-New Brunswick.
“CrAssphages are the most abundant viruses infecting bacteria in the human gut. As such, they likely control our intestinal community of microbes (the microbiome),” said Professor Severinov.
“Understanding how these tiny viruses infect bacteria may allow scientists to control and manipulate the makeup of the microbiome, either by increasing the proportion of beneficial bacteria in our intestines or decreasing the number of harmful bacteria, thus promoting health and fighting disease.”
The scientists determined that crAssphages use their own enzyme – an RNA polymerase – to make RNA copies of their genes. All cells, from bacterial to human, use such enzymes for the same purpose. According to Professor Severinov, the enzymes are very similar in all living matter, implying that they are ancient and related by common ancestry.
The experts analyzed the atomic structure of a crAssphage enzyme. They found that it was distinct from other RNA polymerases yet closely resembled an enzyme in humans that is involved in RNA interference. This interference is known to silence the function of some genes and may lead to certain diseases.
“This is a startling result. It suggests that enzymes of RNA interference, a process that was thought to occur only in cells of higher organisms, were ‘borrowed’ from an ancestral bacterial virus early in evolution,” explained Professor Severinov. “The result provides a glimpse of how cells of higher organisms evolved by mixing and matching components of simpler cells and even their viruses.”
“In addition to deep evolutionary insights, phage (viral) enzymes such as crAssphage RNA polymerase may be used in synthetic biology to generate genetic circuits that do not exist in nature.”
“We are now trying to match the thousands of different crAssphage viruses in our gut with the bacterial hosts they infect. By using just the ‘right’ bacterial virus, we will be able to get rid of bacteria it infects, which will allow us to alter the composition of the gut microbiome in a targeted way.”
The study is published in the journal Nature.
By Chrissy Sexton, Earth.com Staff Writer