Human health and disease are influenced by gut microbes. However, there are no tools that can study the relationship between microbial activity and host physiology. On April 20, a couple of studies on mice published in the journal Cell helped researchers to understand how it can visualize multiple bacterial strains in the gut. The technique they used was the expression of unique blends of fluorescent proteins. It helped the experts to identify the exact location of the bacteria in the gut, totally based on their colors. Moreover, the tools also enabled controlling the bacterial gene activity in both real time as well as in particular places.

"We found that tools from synthetic biology can allow us to ask new questions about the gut microbiota," says Andrew Goodman of Yale University School of Medicine, senior author of one of the studies. "We also imagine these strategies may provide a starting point for on-demand delivery of therapeutics or other molecules from the microbiota," according to Phys.org.

Although sequencing technology has been used in order to make experts understand the bacterial species in the gut, tools to harness and manipulate the gut microbiome are not accessible. Some model species such as Escherichia coli use some of the tools. However, they cannot be applied to the Bacteroides, the genus that is most abundant inside residents of the United States.

The bacteria in the gut are in hundreds. They play a different role in the subject's health and nutrition and are always in competition with other microbial species in the gut for nutrients, according to Authority Nutrition. A technique and tools to engineer Bacteroides were employed by Justin Sonnenburg of the Stanford University School of Medicine and his team. They thus simultaneously identified multiple bacterial strains.

With the help of tools including synthetic promoters, or DNA sequences that initiated gene transcription, experts managed to engineer genetically six diverse Bacteroides species that could create unknown and unique blends of a red fluorescent protein (RFP) called mCherry and green fluorescent protein (GFP). The engineered species were introduced into mice created in a germ-free environment. After a fortnight, some sections of the colon tissue harnessed a fluorescence microscope that could locate the bacteria in various parts of the gut.

YouTube/Seeker