Science Current Events | Science News | Brightsurf.com
 

A toxic menu

April 18, 2012
In a study published in the journal Proceedings of the National Academy of Science, scientists from the Max Planck Institute for Marine Microbiology in Bremen and Greifswald University, together with colleagues from Freiburg, Italy and the USA, have revealed that a small marine worm, faced with a scarce food supply in the sandy sediments it lives in off the coast of Elba, must deal with a highly poisionous menu: this worm lives on carbon monoxide and hydrogen sulphide.

The worm, Olavius algarvensis, can thrive on these poisons thanks to millions of symbiotic bacteria that live under its skin. They use the energy from carbon monoxide and hydrogen sulphide to produce food for the worm. The symbionts do this just like plants by fixing carbon dioxide into carbohydrates but instead of using light energy from the sun, the symbionts use the energy from chemical compounds like carbon monoxide. "They do this so effectively, that the worm has lost its entire digestive system, including its mouth and gut, during the course of evolution, and feeds only through its symbionts", explains Nicole Dubilier, Head of the Symbiosis Group at the Bremen-based Max Planck Institute.

Carbon monoxide and hydrogen sulphide, however, are by no means the only energy sources this worm can live on. Some of the symbiotic bacteria in the worm can take up hydrogen and organic nutrients from the environment, even if these are present in only tiny amounts. Olavius algarvensis also has other tricks up its sleeve that allow it to survive in its nutrient-poor environment: in contrast to most animals, which are not capable of recycling their waste products and must excrete them, the worm can make further use of these, again thanks to its symbiotic microbes. The symbionts are true recycling masters when it comes to use products that still contain a lot of energy for their own purposes, but are no longer any use to the worm. "This is the reason why the worm has been able to not only reduce its digestive system, but also its kidney-like excretory organs", stresses Dubilier, "something that has not been discovered in any other marine animal."

For their investigations, the researchers used a combination of cutting-edge techniques, such as metaproteomics and metabolomics, which make it possible to analyse a large proportion of the proteins and metabolic products in an organism. Metaproteomic analysis presented a particular challenge, as it required the researchers to separate the cells of the symbionts and the host. Thomas Schweder from the Institute of Pharmacy at Greifswald University explains: "Using metaproteomics, we were able to identify thousands of proteins and assign them to the individual partners in the symbiosis. This gave us direct insights into the metabolism of the bacterial symbionts and their interactions with the host."

The researchers were very surprised when their analyses revealed that the worm has large amounts of proteins that allow it to use carbon monoxide as an energy source, because this gas is so poisonous. "Also, we couldn't imagine that carbon monoxide is present in the worm's environments", says Manuel Kleiner, a doctoral student in Nicole Dubilier's research group, "so we were amazed to find such unusually high concentrations of carbon monoxide in the Elba sandy sediments."

Nicole Dubilier has been working with the worm for more than 15 years: "We have known for quite some time that the symbiotic bacteria in Olavius algarvensis can interact with one another to use the energy-rich sulphur compounds to gain energy." But it is only now that the researchers have been able to work out other metabolic pathways - and to discover new energy sources. The study highlights the importance of complementing metagenomic analyses with metaproteomics and metabolomics. "The worm provides us with an example of the power of evolution. Over the course of millions of years, adaptation and selection have led to the development of an optimally adapted host-symbiont system. And these seemingly modest worms are an excellent model for a better understanding of other complex symbioses, such as those of the human gut", says Dubilier.

Max-Planck-Gesellschaft


Related Carbon Monoxide Current Events and Carbon Monoxide News Articles


New concept of fuel cell for efficiency and environment
The Center for Nanoparticle Research at the Institute for Basic Science (IBS) has succeeded in proposing a new method to enhance fuel cell efficiency with the simultaneous removal of toxic heavy metal ions.

Rx Drugs, 'Bath Salts,' Fake Pot and Laundry Pods Lead Millions to Call Poison Centers
National Poison Control Center data from 2012 show that poisonings from prescription drugs are the leading cause of injury death in the United States, and that poisonings from "bath salts," synthetic marijuana and laundry detergent pods are emerging threats to public health.

College students believe hookah safer alternative to cigarette smoking, USF study finds
Despite emerging evidence otherwise, many college students consider hookah smoking safer than smoking cigarettes, reports a University of South Florida (USF) College of Public Health study published this month by the Centers for Disease Control and Prevention (CDC).

The gold standard
Precious elements such as platinum work well as catalysts in chemical reactions, but require large amounts of metal and can be expensive.

Single-atom gold catalysts may offer path to low-cost production of fuel and chemicals
New catalysts designed and investigated by Tufts University School of Engineering researchers and collaborators from other university and national laboratories have the potential to greatly reduce processing costs in future fuels, such as hydrogen.

E-cigarettes significantly reduce tobacco cravings
Electronic cigarettes offer smokers a realistic way to kick their tobacco smoking addiction. In a new study published in the International Journal of Environmental Research and Public Health, scientists at KU Leuven report that e-cigarettes successfully reduced cravings for tobacco cigarettes, with only minimal side effects.

Scientists uncover a role for carbon monoxide in battling bacterial infections
The innate immune system serves as the body's specialized armed forces division, comprised of a host of defense mechanisms used to battle bacterial infections.

Figuring Out How We Get the Nitrogen We Need
Nitrogen is an essential component of all living systems, playing important roles in everything from proteins and nucleic acids to vitamins.

New window on the early universe
Using two world-class supercomputers, the researchers were able to demonstrate the effectiveness of their approach by simulating the formation of a massive galaxy at the dawn of cosmic time.

Getting To Know Super-Earths
"If you have a coin and flip it just once, what does that tell you about the odds of heads versus tails?" asks Heather Knutson, assistant professor of planetary science at Caltech. "It tells you almost nothing. It's the same with planetary systems," she says.
More Carbon Monoxide Current Events and Carbon Monoxide News Articles

© 2015 BrightSurf.com