Protein analysis investigates marine worm community

May 09, 2012
Olavius algarvensis, a marine worm (seen in inset) found in shallow waters off the coast of Elba, Italy, relies on microbes that live in its body to process its waste and provide energy. ORNL researchers used metaproteomics to help understand this microbial community, which serves as a model for more complex communities such as those found in humans. (Photo credit: Christian Lott/HYDRA/Max Planck Institute for Marine Microbiology, Bremen)

(Phys.org) -- Techniques used by researchers from the Department of Energy's Oak Ridge National Laboratory to analyze a simple marine worm and its resident bacteria could accelerate efforts to understand more complex microbial communities such as those found in humans.

In a paper published in the , a multi-institutional research team analyzed the proteins found in a marine worm known as Olavius algarvensis. The worm lacks a digestive system and relies on microbes that live in its body to process its waste and provide energy. Previous research, however, had not untangled the metabolic details of this mutually beneficial, or symbiotic, relationship.

"This community is like the simplest form of the human gut," said coauthor Nathan VerBerkmoes of ORNL. "It is a to understand symbiosis."

While some complex microbial communities such as the human gastrointestinal system contain hundreds of thousands of microbes, the marine worm relies on only four to five bacteria. Understanding the simple network of relationships between the worm and its symbionts, however, still required novel techniques to analyze the functions of a whole system rather than individual parts.

"Very often, you'll have a community that does function x," VerBerkmoes said. "But if you try to isolate any one of those microbes out of the community and get it to do that function, one microbe alone can't do it. Furthermore these cannot be easily isolated and studied by traditional molecular approaches. "

To unravel the interactions of the worm community, an ORNL team led by VerBerkmoes used metaproteomics, a form of analysis that identifies and categorizes the proteins in an organism's cell. Genomics, which yields the DNA sequence of an organism, can predict a cell's behavior, whereas proteomics gives scientists a real-time snapshot of what actually happens in the cell's metabolism.

The combination of genomics and proteomics can also help explain apparent redundancies in a system where several organisms appear at first glance to perform the same function.

"One of the key questions in metagenomic analyses of complex symbiotic consortia, including those of the , is why there is so much functional redundancy," said lead author Nicole Dubilier of the Max Planck Institute for . "Our metaproteomic analyses of the bacteria found in O. algarvensis indicate functional differences in the metabolism of two despite their genetic similarities. This appears to be a common theme in ."

Metaproteomics provided indirect evidence for the research team's hypotheses about the worm community's metabolism, such as the potential use of hydrogen and carbon monoxide as energy sources. VerBerkmoes adds that while their analysis rapidly provided a broad overview of the system, the techniques do not confirm the specifics of individual protein behavior or function, which must be established via further direct biochemical studies.

The research is published as "Metaproteomics of a gutless and its symbiotic microbial community reveal unusual pathways for carbon and energy use." Coauthors include ORNL's Jacque Young, Yun-Juan Chang and Manesh Shah, and researchers from the Max Planck Institute for Marine Microbiology, the University of Greifswald, the University of Freiburg, the Institute of Marine Biotechnology in Greifswald, and the HYDRA Institute for Marine Sciences. The project was lead by Manuel Kleiner and Nicole Dubilier from the Max Planck Institute for Marine Microbiology.

Explore further: Top Japan lab dismisses ground-breaking stem cell study

More information: The entire proteome dataset is available for open access at: compbio.ornl.gov/olavius_algar… mbiont_metaproteome/

Provided by Oak Ridge National Laboratory

not rated yet

Related Stories

A unique marine symbiosis is studied

Sep 23, 2005

A symbiosis of bacteria and a marine worm found by Monterey Bay, Calif., researchers is believed the only one solely using marine mammals for nutrition.

It Takes 'Guts' to Explore the Next Proteomics Frontier

Jul 16, 2010

(PhysOrg.com) -- In the quest to find new sources of biofuel, researchers are studying one of the most efficient bioreactors on earth: the termite. The same insect that causes distress to homeowners with its ...

Bigelow laboratory scientists doach to study marine microbes

May 21, 2007

In a paper published this month in the Proceedings of the National Academy of Sciences, Dr. Ramunas Stepanauskas and Dr. Michael Sieracki have proven a new method of identifying genetic codes of ocean microbes from a sing ...

How bacteria keep us healthy

Jan 25, 2011

(PhysOrg.com) -- Joerg Graf is studying medicinal leeches for clues about how changes in diet affect microorganisms in the digestive tract.

Recommended for you

Top Japan lab dismisses ground-breaking stem cell study

17 hours ago

Japan's top research institute on Friday hammered the final nail in the coffin of what was once billed as a ground-breaking stem cell study, dismissing it as flawed and saying the work could have been fabricated.

Research sheds light on what causes cells to divide

Dec 24, 2014

When a rapidly-growing cell divides into two smaller cells, what triggers the split? Is it the size the growing cell eventually reaches? Or is the real trigger the time period over which the cell keeps growing ...

Locking mechanism found for 'scissors' that cut DNA

Dec 24, 2014

Researchers at Johns Hopkins have discovered what keeps an enzyme from becoming overzealous in its clipping of DNA. Since controlled clipping is required for the production of specialized immune system proteins, ...

Scrapie could breach the species barrier

Dec 24, 2014

INRA scientists have shown for the first time that the pathogens responsible for scrapie in small ruminants (prions) have the potential to convert the human prion protein from a healthy state to a pathological ...

Extracting bioactive compounds from marine microalgae

Dec 24, 2014

Microalgae can produce high value health compounds like omega-3s , traditionally sourced from fish. With declining fish stocks, an alternative source is imperative. Published in the Pertanika Journal of Tr ...

User comments : 0

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.