In a paper published in the Proceedings of the National Academy of Sciences, 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.
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)
"This community is like the simplest form of the human gut," said coauthor Nathan VerBerkmoes of ORNL. "It is a model system 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 microbes 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 human gut, is why there is so much functional redundancy," said lead author Nicole Dubilier of the Max Planck Institute for Marine Microbiology. "Our metaproteomic analyses of the bacteria found in O. algarvensis indicate functional differences in the metabolism of two symbionts despite their genetic similarities. This appears to be a common theme in microbial communities."
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 marine worm 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.
The entire proteome dataset is available for open access at: http://compbio.ornl.gov/olavius_algarvensis_symbiont_metaproteome/.
The study was supported by the Max Planck Society, by the Laboratory Directed Research and Development program at Oak Ridge National Laboratory, and by a grant of the German Research Foundation.
ORNL is managed by UT-Battelle for the Department of Energy's Office of Science. DOE's Office of Science is the single largest supporter of basic research in the physical sciences in the United States, and is working to address some of the most pressing challenges of our time. For more information, please visit http://science.energy.gov.
Morgan McCorkle | EurekAlert!
New yeast species discovered in Braunschweig, Germany
13.12.2019 | Leibniz-Institut DSMZ-Deutsche Sammlung von Mikroorganismen und Zellkulturen GmbH
Saliva test shows promise for earlier and easier detection of mouth and throat cancer
13.12.2019 | Elsevier
Vaccinia viruses serve as a vaccine against human smallpox and as the basis of new cancer therapies. Two studies now provide fascinating insights into their unusual propagation strategy at the atomic level.
For viruses to multiply, they usually need the support of the cells they infect. In many cases, only in their host’s nucleus can they find the machines,...
More than one hundred and fifty years have passed since the publication of James Clerk Maxwell's "A Dynamical Theory of the Electromagnetic Field" (1865). What would our lives be without this publication?
It is difficult to imagine, as this treatise revolutionized our fundamental understanding of electric fields, magnetic fields, and light. The twenty original...
In a joint experimental and theoretical work performed at the Heidelberg Max Planck Institute for Nuclear Physics, an international team of physicists detected for the first time an orbital crossing in the highly charged ion Pr⁹⁺. Optical spectra were recorded employing an electron beam ion trap and analysed with the aid of atomic structure calculations. A proposed nHz-wide transition has been identified and its energy was determined with high precision. Theory predicts a very high sensitivity to new physics and extremely low susceptibility to external perturbations for this “clock line” making it a unique candidate for proposed precision studies.
Laser spectroscopy of neutral atoms and singly charged ions has reached astonishing precision by merit of a chain of technological advances during the past...
The ability to investigate the dynamics of single particle at the nano-scale and femtosecond level remained an unfathomed dream for years. It was not until the dawn of the 21st century that nanotechnology and femtoscience gradually merged together and the first ultrafast microscopy of individual quantum dots (QDs) and molecules was accomplished.
Ultrafast microscopy studies entirely rely on detecting nanoparticles or single molecules with luminescence techniques, which require efficient emitters to...
Graphene, a two-dimensional structure made of carbon, is a material with excellent mechanical, electronic and optical properties. However, it did not seem suitable for magnetic applications. Together with international partners, Empa researchers have now succeeded in synthesizing a unique nanographene predicted in the 1970s, which conclusively demonstrates that carbon in very specific forms has magnetic properties that could permit future spintronic applications. The results have just been published in the renowned journal Nature Nanotechnology.
Depending on the shape and orientation of their edges, graphene nanostructures (also known as nanographenes) can have very different properties – for example,...
03.12.2019 | Event News
15.11.2019 | Event News
15.11.2019 | Event News
13.12.2019 | Physics and Astronomy
13.12.2019 | Physics and Astronomy
13.12.2019 | Materials Sciences