Navigation Links
Newly discovered gut virus lives in half the world's population

Odds are, theres a virus living inside your gut that has gone undetected by scientists for decades. A new study led by researchers at San Diego State University has found that more than half the worlds population is host to a newly described virus, named crAssphage, which infects one of the most common types of gut bacteria, Bacteroidetes. This phylum of bacteria is thought to be connected with obesity, diabetes and other gut-related diseases. The research appears today in Nature Communications.

Robert A. Edwards, a bioinformatics professor at SDSU, and his colleagues stumbled upon the discovery quite by accident. Working with visiting researcher and corresponding author on the study Bas E. Dutilh, now at Radboud University Medical Center in The Netherlands, the researchers were using results from previous studies on gut-inhabiting viruses to screen for new viruses.

In the DNA fecal samples from 12 different individuals, they noticed a particular cluster of viral DNA, about 97,000 base pairs long, that the samples all had in common. When Edwards and his colleagues checked this discovery against a comprehensive listing of known viruses, they came up empty.

The researchers then screened for the virus across the database of the National Institute of Healths Human Microbiome Project (HMP), and Argonne National Laboratory's MG-RAST database, and again found it in abundance in samples derived from human feces.

To prove that the viral DNA they discovered in their computer data actually exists in nature, fellow SDSU virologist John Mokili used a technique known as DNA amplification to locate the virus in the original samples used to build NIHs database.

So we have a biological proof that the virus they found with the computer actually exists in the samples, Mokili said.

This was a new virus that about half the sampled people had in their bodies that nobody knew about.

Its not unusual to go looking for a novel virus and find one, Edwards said. But its very unusual to find one that so many people have in common. The fact that its flown under the radar for so long is very strange.

An ancient virus

The fact that its so widespread indicates that it probably isnt a particularly young virus, either.

Weve basically found it in every population weve looked at, Edwards said. As far as we can tell, its as old as humans are.

He and his team named the virus crAssphage, after the cross-assembly software program used to discover it.

Some of the proteins in crAssphages DNA are similar to those found in other well-described viruses. That allowed Edwards team to determine that their novel virus is one known as a bacteriophage, which infects and replicates inside bacteriaand using innovative bioinformatic techniques, they predicted that this particular bacteriophage proliferates by infecting a common phylum of gut bacteria known as Bacteriodetes.

Gut punch

Bacteriodetes bacteria live toward the end of the intestinal tract, and they are suspected to play a major role in the link between gut bacteria and obesity. What role crAssphage plays in this process will be a target of future research.

Further details about crAssphage have been difficult to come by. Its unknown how the virus is transmitted, but the fact that it was not found in very young infants fecal samples suggests that it is not passed along maternally, but acquired during childhood. The makeup of the viral DNA suggests that its circular in structure. Further laboratory work has confirmed that the viral DNA is a singular entity, but its proven difficult to isolate.

We know its there, but we cant capture it quite yet, Edwards said.

Once the virus is isolated, he hopes to delve into its role in obesity. Its possible the virus in some way mediates the activity of Bacteriodetes colonies, but whether crAssphage promotes or suppresses obesity-related processes in the gut remains to be seen.

The virus might also be used to prevent or mitigate other diseases affected by the gut such as diabetes and gastroenterological maladies.

Once these processes are better understood, Edwards envisions one day the possibility of personalized medicine based on this virus.

This could be a key to personalized phage medicine, he said. In individuals, we could isolate your particular strain of the virus, manipulate it to target harmful bacteria, then give it back to you.


Contact: Natalia Elko
San Diego State University

Related biology news :

1. When temperatures get cold, newly-discovered process helps fruit flies cope
2. Die-offs of band-tailed pigeons connected to newly discovered parasite
3. Newly identified gene provides reliable visual cue for oil palm fruit ripeness
4. Newly discovered paddle prints show how ancient sea reptiles swam
5. Newly identified B-cell selection process adds to understanding of antibody diversity
6. Newly identified brain cancer mutation will aid drug development
7. Newly found dinosaur is long-nosed cousin of Tyrannosaurus rex
8. Newly discovered molecule may offer hope for immune disorders and runaway inflammation
9. Newly identified small-RNA pathway defends genome against the enemy within
10. Newly discovered catalyst could lead to the low-cost production of clean methanol
11. Newly discovered marsupial the victim of fatal attraction
Post Your Comments:
(Date:11/11/2015)... , Nov. 11, 2015   MedNet Solutions , ... spectrum of clinical research, is pleased to announce that it ... Clinical Trials (PCT) event, to be held November 17-19 ... able to view live demonstrations of iMedNet ... learn how iMedNet has been able to deliver ...
(Date:11/4/2015)... ALBANY, New York , November 4, 2015 /PRNewswire/ ... According to a new market report published by Transparency ... Size, Share, Growth, Trends and Forecast 2015 - 2022", ... value of US$ 30.3 bn by 2022. The market ... during the forecast period from 2015 to 2022. Rising ...
(Date:10/29/2015)... 2015  Rubicon Genomics, Inc., today announced an ... its DNA library preparation products, including the ThruPLEX ... Plasma-seq kit. ThruPLEX Plasma-seq has been optimized for ... libraries for liquid biopsies--the analysis of cell-free circulating ... in cancer and other conditions. Eurofins Scientific is ...
Breaking Biology News(10 mins):
(Date:11/30/2015)... Partnership includes an MPP ... the u niversity , s Solid Drug Nanoparticle (SDN) ... - up through cost cuts ... , where licensees based anywhere in the world will have the right to make, ... Africa , where licensees based anywhere in the world will have the right ...
(Date:11/30/2015)... ... November 30, 2015 , ... ... touring exhibition Jurassic World: The Exhibition, opening in March 2016 at Melbourne Museum ... a worldwide tour including several North American tour dates. The Exhibition is based ...
(Date:11/30/2015)... , Nov. 30, 2015  Aytu BioScience, Inc. (OTCQB: ... and related conditions, will present at two upcoming investor ... an interactive real-time virtual conference, to be held December ... Conference, to be held December 2 nd & ... and streamed live via webcast. ...
(Date:11/30/2015)... TIKVAH, Israel , Nov. 30, 2015 /PRNewswire/ ... a leading developer of adult stem cell technologies for neurodegenerative ... Ltd., has been awarded an additional grant of approximately $735,000 ... Scientist (OCS). This grant, the second this year, brings the ... approximately $1.8 million (approximately NIS7 million).  ...
Breaking Biology Technology: