Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Microbial Companions of Humans and Animals Are Highly Specialized

13.08.2015

Humans and animals are never alone. Everyone is host to over two thousand different species of microbes, of which most colonize our bodies only after we are born. One would assume that the generalists among them have an advantage. Zoologists from the Department of Environmental Sciences at the University of Basel have now shown that the opposite is the case. Microbial communities living on humans and animals are mostly dominated by specialists.

It has long been known that almost all organisms have microbial companions. However, only about ten years ago did researchers find out that these bacterial communities are extremely rich in species. Humans and other mammals are often hosts to several thousand species, and even minute organisms like water fleas can carry over one hundred species.


Microorganisms like these bacteria on the skin of a small crustacean are the constant companions of humans and animals.

© University of Basel

This knowledge only became available by the use of genetic methods, that allowed researchers to sequence all genes of a single ecosystem (for example of the human intestine) at once. Data resulting from this method was also analyzed for the new study of the research group of Dieter Ebert, Zoologist from the Department of Environmental Sciences at the University of Basel.

Specialists or generalists?

The initial question was how specialized these microbes are. Since most bacteria only get recruited after their hosts' birth, one would assume that most of them are generalists. After all, microbes able to live in different environments and on a variety of hosts would have a significant advantage over specialists.

However, earlier studies had already shown that microbial communities differ between different hosts or habitats. However, why these differences occur was unknown. Some researchers assumed that even though hosts are colonized by several microbe species, only a few of them are successful.

The team of researchers around Dieter Ebert hypothesized that the successful microbes are specialists. Meaning that the successful species are those that prefer one specific host, where they then occur locally in great numbers. To test their thesis they developed a statistical method allowing them to align the relative abundance of a specific bacteria species with the degree of its local specificity.

They applied their new method to three very different data sets: Zooplankton from the Ägelsee pond, near Frauenfeld in Switzerland, different human habitats (such as ear, nose, mouth and arm pit) and a set from several ecosystems including water and sediment samples from fresh as well as salt water.

Specialists are more abundant locally

All three data sets revealed the same results: locally abundant microbes are local specialists. And vice versa: the smaller the relative abundance of one species, the more likely is it found in several habitats. Generalists are everywhere but nowhere in abundance, whereas specialists only occur abundant locally.

The journal Ecology Letters published the study financed by an Advanced Investigator Grant of the European Research Council today. The findings have far-reaching implications for our understanding of the structure of biodiversity in microbial ecosystems and they open the doors for further research of habitat-specific ecologic functions of microbes.

Original source

Mahendra Mariadassou, Samuel Pichon and Dieter Ebert
Microbial ecosystems are dominated by specialist taxa
Ecology Letters (2015), doi: 10.1111/ele.12478

Further information

Dieter Ebert, University of Basel, Department of Environmental Sciences, Zoology, phone +41 61 267 03 60/61, email: dieter.ebert@unibas.ch

Weitere Informationen:

https://www.unibas.ch/en/News-Events/News/Uni-Research/Microbial-Companions-of-H...

Olivia Poisson | Universität Basel

More articles from Life Sciences:

nachricht 'Y' a protein unicorn might matter in glaucoma
23.10.2017 | Georgia Institute of Technology

nachricht Microfluidics probe 'cholesterol' of the oil industry
23.10.2017 | Rice 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: Salmonella as a tumour medication

HZI researchers developed a bacterial strain that can be used in cancer therapy

Salmonellae are dangerous pathogens that enter the body via contaminated food and can cause severe infections. But these bacteria are also known to target...

Im Focus: Neutron star merger directly observed for the first time

University of Maryland researchers contribute to historic detection of gravitational waves and light created by event

On August 17, 2017, at 12:41:04 UTC, scientists made the first direct observation of a merger between two neutron stars--the dense, collapsed cores that remain...

Im Focus: Breaking: the first light from two neutron stars merging

Seven new papers describe the first-ever detection of light from a gravitational wave source. The event, caused by two neutron stars colliding and merging together, was dubbed GW170817 because it sent ripples through space-time that reached Earth on 2017 August 17. Around the world, hundreds of excited astronomers mobilized quickly and were able to observe the event using numerous telescopes, providing a wealth of new data.

Previous detections of gravitational waves have all involved the merger of two black holes, a feat that won the 2017 Nobel Prize in Physics earlier this month....

Im Focus: Smart sensors for efficient processes

Material defects in end products can quickly result in failures in many areas of industry, and have a massive impact on the safe use of their products. This is why, in the field of quality assurance, intelligent, nondestructive sensor systems play a key role. They allow testing components and parts in a rapid and cost-efficient manner without destroying the actual product or changing its surface. Experts from the Fraunhofer IZFP in Saarbrücken will be presenting two exhibits at the Blechexpo in Stuttgart from 7–10 November 2017 that allow fast, reliable, and automated characterization of materials and detection of defects (Hall 5, Booth 5306).

When quality testing uses time-consuming destructive test methods, it can result in enormous costs due to damaging or destroying the products. And given that...

Im Focus: Cold molecules on collision course

Using a new cooling technique MPQ scientists succeed at observing collisions in a dense beam of cold and slow dipolar molecules.

How do chemical reactions proceed at extremely low temperatures? The answer requires the investigation of molecular samples that are cold, dense, and slow at...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

3rd Symposium on Driving Simulation

23.10.2017 | Event News

ASEAN Member States discuss the future role of renewable energy

17.10.2017 | Event News

World Health Summit 2017: International experts set the course for the future of Global Health

10.10.2017 | Event News

 
Latest News

Microfluidics probe 'cholesterol' of the oil industry

23.10.2017 | Life Sciences

Gamma rays will reach beyond the limits of light

23.10.2017 | Physics and Astronomy

The end of pneumonia? New vaccine offers hope

23.10.2017 | Health and Medicine

VideoLinks
B2B-VideoLinks
More VideoLinks >>>