Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Bacteria use ’molecular lasso’ to cop copper

10.09.2004


The bacteria that destroy about one-third of the potent greenhouse gas methane before it can reach the atmosphere use a neat trick to gather a key nutrient for the job. They produce a small organic compound and release it into the surrounding environment, where it "lassos" atoms of copper. The bacteria then reabsorb the compound and use the copper as a weapon against methane, from which they extract energy. The crystal structure of the compound--called methanobactin--will be reported in the Sept. 10 issue of Science. The research was led by Hyung J. Kim, who did much of the work as a graduate student at the University of Kansas and is now a postdoctoral associate at the University of Minnesota College of Biological Sciences.



Methanobactin may have antibacterial properties, and its ability to absorb copper may find application in the semiconductor industry, which needs copper-free water. The bacteria that make methanobactin are quite common. "These bacteria are often found in rice paddies and wetlands," said Kim. "Methane is produced in the bottom muck and diffuses into the water, where these bacteria live. The bacteria sequester the methane and turn it into methyl alcohol."

According to estimates made in the 1990s, the amount of methane produced from all sources worldwide is about 120 billion tons per year, said Kim. About 40 percent comes from paddies and wetlands, and the methane-eating bacteria, known as methanotrophs, remove 80 to 90 percent of it. That translates to a methane diet of close to 43 billion tons a year.


Playing a pivotal role in this drama is the methanobactin molecule, a tiny, pyramid-shaped compound with a cleft that holds a single atom of copper in place. The bacteria churn out methanobactin molecules in large numbers and send them into the environment to fetch copper. When the compound returns with its booty, it is thought that the copper is incorporated into molecules of a key enzyme that converts methane to methyl alcohol. A very reactive atom, copper is just the ticket for metabolizing methane, which--chemically speaking--is a hard nut to crack. Their reactivity also makes copper atoms toxic to the bacteria. Thus, methanobactin serves to keep copper under control and protect the bacterial cells from it.

One piece of the story still to be learned is how the methanobactin is retrieved by bacterial cells, Kim said. The cells apparently latch onto copper-bearing methanobactin molecules, but what happens next isn’t known. Also, unlike a cowboy’s lasso, methanobactin has no tether to its mother cell. Therefore, when bacterial cells release their methanobactin molecules, they probably never see them again; instead, they take delivery of copper from methanobactin released by other cells of the same species. Thus, copper gathering amounts to a bacterial free-trading market.

Methanobactin also seems to keep other bacteria out of the market.

"Synthesized compounds analogous to some parts of the methanobactin molecule have been shown to be antibacterial," said Kim. "Researchers in the laboratory of Alan DiSpirito at Iowa State University are exploring the antibacterial properties of this compound."

Besides Kim, co-authors of the Science paper include DiSpirito and David Graham, who was Kim’s adviser at the time the work was done and is an associate professor of civil, architectural and environmental engineering at the University of Kansas. Kim is currently working in the laboratory of Alan Hooper, professor of biochemistry, molecular biology and biophysics at the University of Minnesota. The work was supported by the National Science Foundation, the U.S. Department of Energy and the KU (University of Kansas) Research Development Fund.

Deane Morrison | EurekAlert!
Further information:
http://www.umn.edu

More articles from Life Sciences:

nachricht How brains surrender to sleep
23.06.2017 | IMP - Forschungsinstitut für Molekulare Pathologie GmbH

nachricht A new technique isolates neuronal activity during memory consolidation
22.06.2017 | Spanish National Research Council (CSIC)

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Can we see monkeys from space? Emerging technologies to map biodiversity

An international team of scientists has proposed a new multi-disciplinary approach in which an array of new technologies will allow us to map biodiversity and the risks that wildlife is facing at the scale of whole landscapes. The findings are published in Nature Ecology and Evolution. This international research is led by the Kunming Institute of Zoology from China, University of East Anglia, University of Leicester and the Leibniz Institute for Zoo and Wildlife Research.

Using a combination of satellite and ground data, the team proposes that it is now possible to map biodiversity with an accuracy that has not been previously...

Im Focus: Climate satellite: Tracking methane with robust laser technology

Heatwaves in the Arctic, longer periods of vegetation in Europe, severe floods in West Africa – starting in 2021, scientists want to explore the emissions of the greenhouse gas methane with the German-French satellite MERLIN. This is made possible by a new robust laser system of the Fraunhofer Institute for Laser Technology ILT in Aachen, which achieves unprecedented measurement accuracy.

Methane is primarily the result of the decomposition of organic matter. The gas has a 25 times greater warming potential than carbon dioxide, but is not as...

Im Focus: How protons move through a fuel cell

Hydrogen is regarded as the energy source of the future: It is produced with solar power and can be used to generate heat and electricity in fuel cells. Empa researchers have now succeeded in decoding the movement of hydrogen ions in crystals – a key step towards more efficient energy conversion in the hydrogen industry of tomorrow.

As charge carriers, electrons and ions play the leading role in electrochemical energy storage devices and converters such as batteries and fuel cells. Proton...

Im Focus: A unique data centre for cosmological simulations

Scientists from the Excellence Cluster Universe at the Ludwig-Maximilians-Universität Munich have establised "Cosmowebportal", a unique data centre for cosmological simulations located at the Leibniz Supercomputing Centre (LRZ) of the Bavarian Academy of Sciences. The complete results of a series of large hydrodynamical cosmological simulations are available, with data volumes typically exceeding several hundred terabytes. Scientists worldwide can interactively explore these complex simulations via a web interface and directly access the results.

With current telescopes, scientists can observe our Universe’s galaxies and galaxy clusters and their distribution along an invisible cosmic web. From the...

Im Focus: Scientists develop molecular thermometer for contactless measurement using infrared light

Temperature measurements possible even on the smallest scale / Molecular ruby for use in material sciences, biology, and medicine

Chemists at Johannes Gutenberg University Mainz (JGU) in cooperation with researchers of the German Federal Institute for Materials Research and Testing (BAM)...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Plants are networkers

19.06.2017 | Event News

Digital Survival Training for Executives

13.06.2017 | Event News

Global Learning Council Summit 2017

13.06.2017 | Event News

 
Latest News

Quantum thermometer or optical refrigerator?

23.06.2017 | Physics and Astronomy

A 100-year-old physics problem has been solved at EPFL

23.06.2017 | Physics and Astronomy

Equipping form with function

23.06.2017 | Information Technology

VideoLinks
B2B-VideoLinks
More VideoLinks >>>