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 mePage: 1 2 Related biology news :1
Contact: Deane Morrison
University of Minnesota
. Bacterial protein recycling factor possible key to new class of antibiotics2
. Bacteria spill their guts to aid researchers in quest for new antibiotics3
. Bacteria live in the esophagus!4
. Bacteria lingering in body may pose future food poisoning risks, Stanford study finds5
. Bacteria discoveries could resemble Mars, other planets6
. Bacterial relationships revealed7
. Bacteria-eating viruses may spread some infectious diseases8
. Bacteria convert food processing waste to hydrogen9
. Bacterial viruses make cheap easy vaccines10
. Bacterial infections alter allergic response11
. Bacteria cant do their thing if they dont have cling