Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Oregon study suggests some gut microbes may be keystones of health

12.11.2015

Study using zebrafish finds the abundance of bacteria is not the driving force for regulating a balanced and healthy environment

University of Oregon scientists have found that strength in numbers doesn't hold true for microbes in the intestines. A minority population of the right type might hold the key to regulating good health.


A University of Oregon study finds abundance does not dictate the immune response to bacteria in the guts of zebrafish. This graphic depicts immune response (neutrophils, shown in green) to separate bacterial species, and the response when the two bacteria are placed into a germ-free fish gut at the same time.

Courtesy of Annah S. Rolig

The discovery, based on research using zebrafish raised completely germ free, is reported in a paper published in the Nov. 11 issue of Cell Host & Microbe. The findings provide a path to study the function of each bacterial species in the gut and to eventually, perhaps, predict and prevent disease, says lead author Annah S. Rolig, a postdoctoral researcher in the UO's Institute of Molecular Biology.

In the project, researchers watched for immune response as isolates of species of bacteria, normally associated with healthy zebrafish, were introduced one at a time and in combination into previously germ-free intestines of the fish.

In a telling sequence, one bacterial species, Vibrio, drew numerous neutrophils, which indicated a rapid inflammatory response in one fish. Another species, Shewanella, inserted into a separate germ-free fish barely attracted an immune response. In a third germ-free fish, both species were introduced together and assembled with a ratio of 90- percent Vibrio to 10-percent Shewanella.

The inflammatory response in the third fish was completely controlled by the low-abundance species.

"Until now, we've only been able to capture proportional information, like you'd see displayed in a pie graph, of the makeup of various microbiota, in percentages of their abundance," Rolig said. "Biologists in this field have typically assumed an equal contribution based on that makeup."

Low counts of a bacterial species generally have been discounted in importance, but slight shifts in the ratios of abundant microbe populations have been thought to have roles in obesity, diabetes and inflammatory bowel diseases such as Crohn's disease.

That thinking is now changing, Rolig said. "The contribution of each bacterium is not equal. There is a per-capita effect that needs to be considered."

The keystone - an important participant that functions to regulate a healthy microbiota - may reside in low-abundant bacterial species. The research team found through additional scrutiny that these species secreted molecules - for now unidentified - that allowed them to dampen the immune response to the whole community.

"Now we've shown that these minor members can have a major impact. If we can identify these keystone species, and find that in a disease state one species may be missing, we might be able to go in with a specific probiotic to restore healthy functioning," said Rolig, who also is a scientist in the National Institutes of Health-funded Microbial Ecology and Theory of Animals Center for Systems Biology, known as the META Center, at the UO.

To develop a model to capture per-capita contributions of microbes in a population, Rolig and her co-authors -- biology graduate student Adam R. Burns, microbiologist Brendan Bohannan of the Institute of Ecology and Evolution and biologist Karen Guillemin, director of the META Center -- turned to UO physicist Raghuveer Parthasarathy. His math-driven model, detailed in the paper, provides formulas that predict collective inflammatory responses of combinations of bacteria.

"I'm really proud of this paper because it exemplifies an achievement of one of the major goals of the META Center for Systems Biology, namely to provide a predictive model of how host-microbe systems function," Guillemin said. "This experimental and modeling framework could be readily generalized to more complex systems such as humans, for example to predict disease severity in individuals with inflammatory bowel disease based on the pro-inflammatory capacity of their gut microbes as assayed in cell culture."

###

The National Institutes of Health supported the research through grants P50GMO98911 to support the META Center, IF32DK098884 for a postdoctoral fellowship to Rolig and P01HD22486 that supports the UO's zebrafish facility.

Sources: Annah S. Rolig, postdoctoral research associate, UO Institute of Molecular Biology, 541-346-5999, arolig@uoregon.edu, and Karen Guillemin, professor of biology and director of the META Center for Systems Biology, 541-346-5360, guilleman@molbio.uoregon.edu

Note: The UO is equipped with an on-campus television studio with a point-of-origin Vyvx connection, which provides broadcast-quality video to networks worldwide via fiber optic network. There also is video access to satellite uplink and audio access to an ISDN codec for broadcast-quality radio interviews.

Links:

Paper abstract: http://www.cell.com/cell-host-microbe/abstract/S1931-3128%2815%2900419-9

META Center for Systems Biology: http://meta.uoregon.edu

Institute of Molecular Biology: http://molbio.uoregon.edu

Institute of Ecology and Evolution: http://ie2.uoregon.edu

Guillemin faculty page: http://molbio.uoregon.edu/guillemin/

Media Contact

Jim Barlow
jebarlow@uoregon.edu
541-346-3481

 @UOregonNews

http://uonews.uoregon.edu 

Jim Barlow | EurekAlert!

More articles from Life Sciences:

nachricht Bacteria as pacemaker for the intestine
22.11.2017 | Christian-Albrechts-Universität zu Kiel

nachricht Researchers identify how bacterium survives in oxygen-poor environments
22.11.2017 | Columbia University

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Nanoparticles help with malaria diagnosis – new rapid test in development

The WHO reports an estimated 429,000 malaria deaths each year. The disease mostly affects tropical and subtropical regions and in particular the African continent. The Fraunhofer Institute for Silicate Research ISC teamed up with the Fraunhofer Institute for Molecular Biology and Applied Ecology IME and the Institute of Tropical Medicine at the University of Tübingen for a new test method to detect malaria parasites in blood. The idea of the research project “NanoFRET” is to develop a highly sensitive and reliable rapid diagnostic test so that patient treatment can begin as early as possible.

Malaria is caused by parasites transmitted by mosquito bite. The most dangerous form of malaria is malaria tropica. Left untreated, it is fatal in most cases....

Im Focus: A “cosmic snake” reveals the structure of remote galaxies

The formation of stars in distant galaxies is still largely unexplored. For the first time, astron-omers at the University of Geneva have now been able to closely observe a star system six billion light-years away. In doing so, they are confirming earlier simulations made by the University of Zurich. One special effect is made possible by the multiple reflections of images that run through the cosmos like a snake.

Today, astronomers have a pretty accurate idea of how stars were formed in the recent cosmic past. But do these laws also apply to older galaxies? For around a...

Im Focus: Visual intelligence is not the same as IQ

Just because someone is smart and well-motivated doesn't mean he or she can learn the visual skills needed to excel at tasks like matching fingerprints, interpreting medical X-rays, keeping track of aircraft on radar displays or forensic face matching.

That is the implication of a new study which shows for the first time that there is a broad range of differences in people's visual ability and that these...

Im Focus: Novel Nano-CT device creates high-resolution 3D-X-rays of tiny velvet worm legs

Computer Tomography (CT) is a standard procedure in hospitals, but so far, the technology has not been suitable for imaging extremely small objects. In PNAS, a team from the Technical University of Munich (TUM) describes a Nano-CT device that creates three-dimensional x-ray images at resolutions up to 100 nanometers. The first test application: Together with colleagues from the University of Kassel and Helmholtz-Zentrum Geesthacht the researchers analyzed the locomotory system of a velvet worm.

During a CT analysis, the object under investigation is x-rayed and a detector measures the respective amount of radiation absorbed from various angles....

Im Focus: Researchers Develop Data Bus for Quantum Computer

The quantum world is fragile; error correction codes are needed to protect the information stored in a quantum object from the deteriorating effects of noise. Quantum physicists in Innsbruck have developed a protocol to pass quantum information between differently encoded building blocks of a future quantum computer, such as processors and memories. Scientists may use this protocol in the future to build a data bus for quantum computers. The researchers have published their work in the journal Nature Communications.

Future quantum computers will be able to solve problems where conventional computers fail today. We are still far away from any large-scale implementation,...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Ecology Across Borders: International conference brings together 1,500 ecologists

15.11.2017 | Event News

Road into laboratory: Users discuss biaxial fatigue-testing for car and truck wheel

15.11.2017 | Event News

#Berlin5GWeek: The right network for Industry 4.0

30.10.2017 | Event News

 
Latest News

Corporate coworking as a driver of innovation

22.11.2017 | Business and Finance

PPPL scientists deliver new high-resolution diagnostic to national laser facility

22.11.2017 | Physics and Astronomy

Quantum optics allows us to abandon expensive lasers in spectroscopy

22.11.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>