Methanogens play a key role in carbon cycling. When plants die, some of their biomass is trapped in areas that are devoid of oxygen, such as the bottom of lakes.
Methanogens help convert the residual biological material to methane, which other organisms convert to carbon dioxide a product that can be used by plants.
This natural process for producing methane forms the basis for treating municipal and industrial wastes, helps reduce pollution, and provides methane for fuel. The same process allows natural gas production from agricultural residues, a renewable resource.
Methanogens also play an important role in agriculture and human health. They live in the digestive systems of cattle and sheep where they facilitate the digestion of feed consumed in the diet.
Efforts to control methanogens in specific ways may improve feed utilization and enhance the production of meat and milk, researchers say.
Methanogens are additionally a factor in human nutrition. The organisms live in the large intestine, where they enhance the breakdown of food. Some have proposed that restricting this activity of methanogens could help alleviate obesity.
The team investigated an ancient type of methanogen, Methanocaldococcus jannaschii, which lives in deep-sea hydrothermal vents or volcanoes where environmental conditions mimic those that existed on the early Earth.
They found that the protein thioredoxin, which plays a major role in contemporary photosynthesis, could repair many of the organism's proteins damaged by oxygen.
Since methanogens developed before oxygen appeared on earth, the evidence raises the possibility that thioredoxin-based metabolic regulation could have come into play for managing anaerobic life long before the advent of oxygen.
"It is rewarding to see that our decades of research on thioredoxin and photosynthesis are contributing to understanding the ancient pr
|Contact: Zeke Barlow|