Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

The nutritionists within

01.12.2014

Firebugs depend on gut bacteria for vitamin supply. Scientists of the Max Planck Institute for Chemical Ecology in Jena, Germany, found that bacterial symbionts in the insects’ gut produce these vitamins and thereby ensure the host’s metabolic stability.

The vitamin supply provided by the symbionts directly influences the gene regulation of their host: If the bacterial associates are absent, the bugs show a characteristic vitamin deficiency response.


European firebug Pyrrhocoris apterus

Martin Kaltenpoth / Max Planck Institute for Chemical Ecology


African cotton stainer Dysdercus fasciatus

Martin Kaltenpoth / Max Planck Institute for Chemical Ecology

However, the symbiosis between the bugs and their bacteria is not necessarily a harmonious one: The insects are proposed to actively harvest the vitamins from the bacteria by using specific enzymes that burst open the bacterial cell walls.

Microbial partners are important for the nutrition of many insects. They help detoxify and digest food, but also provide essential nutrients that insects need in order to survive. The European firebug Pyrrhocoris apterus and the African cotton stainer Dysdercus fasciatus feed mainly on plant seeds that are poor sources of essential B vitamins.

Scientists of the Max Planck Research Group Insect Symbiosis at the Max Planck Institute for Chemical Ecology in Jena, Germany, together with colleagues at the Friedrich Schiller University, have now found that bacterial symbionts in the insects’ gut produce these vitamins and thereby ensure the host’s metabolic stability and, ultimately, survival.

Interestingly, the vitamin supply provided by the symbionts directly influences the gene regulation of their host: If the bacterial associates are absent, the bugs show a characteristic vitamin deficiency response. However, the symbiosis between the bugs and their bacteria is not necessarily a harmonious one: The insects are proposed to actively harvest the vitamins from the bacteria by using specific enzymes that burst open the bacterial cell walls. (Proceedings of the Royal Society B: Biological Sciences, November 2014).

In their quest for a balanced meal plan, firebugs – and many other animals – depend on dietary supplements. Firebugs are a group of terrestrial insects that includes the ubiquitously found European firebug Pyrrhocoris apterus as well as the agricultural pest, the African cotton stainer Dysdercus fasciatus. As demonstrated previously, firebugs depend on their gut microbes for successful development.

The symbiotic bacteria from the Coriobacteriaceae family provide essential vitamins. Microbe-free bugs suffer high mortality and produce fewer young than bugs that have their microbial partners (see our press release “Bugs need symbiotic bacteria to exploit plant seeds” - http://www.ice.mpg.de/ext/976.html , January 9, 2013).

Controlled experiments by the scientists from Jena implicate the bacterial symbionts in supplementing B vitamins to firebugs as an important feature of this association. Firebugs that lack their symbionts, but are reared on an artificial diet rich in B vitamins do perfectly fine compared to bugs that have their microbes. It is only when B vitamins are eliminated from the artificial diet that symbiont-free bugs are observed to suffer high mortality during their juvenile stages.

What is even more striking is the effect of symbiont absence on the host’s metabolism. “As a condition of nutrient limitation, firebugs that lack their symbionts were found to exhibit a different metabolic profile; one that can be restored either through the artificial supply of B-vitamins into their diet, or by reintroducing the insect to its symbionts,” Hassan Salem, the first author of the study explains. Profiling the expression patterns of host genes revealed that the insect significantly increases the abundance of B vitamin transporters and activation enzymes when reared in the absence of its gut microbes.

As the scientists found out, proteins that carry out the active transport of B vitamins across the gut epithelium and into cells are expressed in higher amounts when the host is lacking these important nutrients, as a means of increasing the efficiency in scraping the scarce vitamins together from the gut content. Supplementing B vitamins into the insect’s diet or reestablishing the symbiotic partnership restores normal expression patterns of those genes.

An examination into the host’s immune response to symbiont presence suggests that firebugs actively harvest their bacterial partners by lysing, or bursting open, the bacterial cells. This enables them to take up the free vitamins from the dead cells. The expression of genes encoding special antimicrobial peptides, specifically, lysozyme, supports this assumption.

“Vitamin supplementation is probably too friendly of a word. Surrendered is somewhat more accurate, given how the host is thought to extract the vitamins from its microbes, it basically exploits the microbes to gain the benefits. Still, since only a fraction of the symbiont population is harvested, the microbes likely benefit from the association with the host by gaining nutrition in the bug’s gut and a secured transmission route to the next generation,” says Hassan Salem.

While strides have been made in our effort to understand the importance of the complex human microbiome, the exact functions of the majority of our gut associates remain unknown, as is their impact on our metabolism and overall physiology. As such, valuable insights can be gained from insects and their often simple and experimentally tractable microbial communities. [HS/MK/AO]

Original Publication:
Salem H, Bauer E, Strauss A, Vogel H, Marz M, Kaltenpoth M. (2014) Vitamin supplementation by gut symbionts ensures metabolic homeostasis in an insect host. Proceedings of the Royal Society B: Biological Sciences. 281, 2014183
http://dx.doi.org/10.1098/rspb.2014.1838

Further Information:
Dr. Martin Kaltenpoth, Max Planck Institute for Chemical Ecology, Hans-Knöll-Straße 8, 07745 Jena, Germany, Tel. +49 3641 57-1800, E-Mail mkaltenpoth@ice.mpg.de
Dr. Hassan Salem, Max Planck Institute for Chemical Ecology, Hans-Knöll-Straße 8, 07745 Jena, Germany, Tel. +49 3641 57-1804, E-Mail hsalem@ice.mpg.de

Picture Requests:
Angela Overmeyer M.A., Max Planck Institute for Chemical Ecology, Hans-Knöll-Str. 8, 07743 Jena, +49 3641 57-2110, overmeyer@ice.mpg.de

Download of high resolution images via http://www.ice.mpg.de/ext/735.html


Weitere Informationen:

http://www.ice.mpg.de/ext/1174.html?&L=0

Angela Overmeyer | Max-Planck-Institut

More articles from Life Sciences:

nachricht Hunting pathogens at full force
22.03.2017 | Helmholtz-Zentrum für Infektionsforschung

nachricht A 155 carat diamond with 92 mm diameter
22.03.2017 | Universität Augsburg

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Giant Magnetic Fields in the Universe

Astronomers from Bonn and Tautenburg in Thuringia (Germany) used the 100-m radio telescope at Effelsberg to observe several galaxy clusters. At the edges of these large accumulations of dark matter, stellar systems (galaxies), hot gas, and charged particles, they found magnetic fields that are exceptionally ordered over distances of many million light years. This makes them the most extended magnetic fields in the universe known so far.

The results will be published on March 22 in the journal „Astronomy & Astrophysics“.

Galaxy clusters are the largest gravitationally bound structures in the universe. With a typical extent of about 10 million light years, i.e. 100 times the...

Im Focus: Tracing down linear ubiquitination

Researchers at the Goethe University Frankfurt, together with partners from the University of Tübingen in Germany and Queen Mary University as well as Francis Crick Institute from London (UK) have developed a novel technology to decipher the secret ubiquitin code.

Ubiquitin is a small protein that can be linked to other cellular proteins, thereby controlling and modulating their functions. The attachment occurs in many...

Im Focus: Perovskite edges can be tuned for optoelectronic performance

Layered 2D material improves efficiency for solar cells and LEDs

In the eternal search for next generation high-efficiency solar cells and LEDs, scientists at Los Alamos National Laboratory and their partners are creating...

Im Focus: Polymer-coated silicon nanosheets as alternative to graphene: A perfect team for nanoelectronics

Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are less stable. Now researchers at the Technical University of Munich (TUM) have, for the first time ever, produced a composite material combining silicon nanosheets and a polymer that is both UV-resistant and easy to process. This brings the scientists a significant step closer to industrial applications like flexible displays and photosensors.

Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are...

Im Focus: Researchers Imitate Molecular Crowding in Cells

Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to simulate these confined natural conditions in artificial vesicles for the first time. As reported in the academic journal Small, the results are offering better insight into the development of nanoreactors and artificial organelles.

Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

International Land Use Symposium ILUS 2017: Call for Abstracts and Registration open

20.03.2017 | Event News

CONNECT 2017: International congress on connective tissue

14.03.2017 | Event News

ICTM Conference: Turbine Construction between Big Data and Additive Manufacturing

07.03.2017 | Event News

 
Latest News

Pulverizing electronic waste is green, clean -- and cold

22.03.2017 | Materials Sciences

Astronomers hazard a ride in a 'drifting carousel' to understand pulsating stars

22.03.2017 | Physics and Astronomy

New gel-like coating beefs up the performance of lithium-sulfur batteries

22.03.2017 | Materials Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>