Viral dark matter exposed: Metagenome database detects phage-derived antibacterial enzyme

July 10, 2020

In a pioneer study published in Cell Host & Microbe - Researchers at Osaka City University and The Institute for Medical Science, The University of Tokyo, reported intestinal bacterial and viral metagenome information from the fecal samples of 101 healthy Japanese individuals. This analysis, leveraging host bacteria-phage associations, detected phage-derived antibacterial enzymes that control pathobionts. As proof-of-concept, phage-derived endolysins are shown to regulate C. difficile infection in mice.

Abnormalities in human intestinal microflora, known as dysbiosis, are connected to various diseases. Altered microbial diversity impairs the beneficial effects of host intestinal microflora, which cause some symbiotic commensal bacteria to acquire virulence traits, proliferate, and become directly involved in the development of disease. These bacteria are referred to as "pathobionts", which are distinct from opportunistic pathogens.

C. difficile, which is a Gram-positive, spore-forming anaerobic bacterium, is a pathobiont and the representative cause of nosocomial diarrhea following antibiotic treatment. Since antibiotic usage has the risk of killing beneficial bacteria and promoting dysbiosis, the development of methods to specifically manipulate intestinal pathobionts is essential.

"Phages were sure to be applicable as a highly specific therapy for intestinal pathobiont elimination", believed Professor Satoshi Uematsu. The infectious associations between phages and bacteria in the human intestine is essential information for the development of phage therapies. Known as "viral dark matter" as it had yet to be understood, researchers obtained metagenome information about bacteria-phage associations from the fecal samples of 101 healthy individuals through the development of a virome analysis pipeline. Based on this information, researchers screened C. difficile-specific phages and identified novel antibacterial enzymes, both in vitro and in vivo.

"The accumulation of more metagenomic information on intestinal phages and bacteria will open up the possibility of developing treatments for a variety of dysbiosis-related diseases", say Dr. Kosuke Fujimoto and Prof. Seiya Imoto.
-end-


Osaka City University

Related Bacteria Articles from Brightsurf:

Siblings can also differ from one another in bacteria
A research team from the University of Tübingen and the German Center for Infection Research (DZIF) is investigating how pathogens influence the immune response of their host with genetic variation.

How bacteria fertilize soya
Soya and clover have their very own fertiliser factories in their roots, where bacteria manufacture ammonium, which is crucial for plant growth.

Bacteria might help other bacteria to tolerate antibiotics better
A new paper by the Dynamical Systems Biology lab at UPF shows that the response by bacteria to antibiotics may depend on other species of bacteria they live with, in such a way that some bacteria may make others more tolerant to antibiotics.

Two-faced bacteria
The gut microbiome, which is a collection of numerous beneficial bacteria species, is key to our overall well-being and good health.

Microcensus in bacteria
Bacillus subtilis can determine proportions of different groups within a mixed population.

Right beneath the skin we all have the same bacteria
In the dermis skin layer, the same bacteria are found across age and gender.

Bacteria must be 'stressed out' to divide
Bacterial cell division is controlled by both enzymatic activity and mechanical forces, which work together to control its timing and location, a new study from EPFL finds.

How bees live with bacteria
More than 90 percent of all bee species are not organized in colonies, but fight their way through life alone.

The bacteria building your baby
Australian researchers have laid to rest a longstanding controversy: is the womb sterile?

Hopping bacteria
Scientists have long known that key models of bacterial movement in real-world conditions are flawed.

Read More: Bacteria News and Bacteria Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.