They might be helping to limit the concentrations of greenhouse gases in the atmosphere and might one day be useful for cleaning up oil spills.
Scientists at The University of Texas at Austin's Marine Science Institute have discovered nearly two dozen new types of microbes, many of which use hydrocarbons such as methane and butane as energy sources to survive and grow, meaning the newly identified bacteria might be helping to limit the concentrations of greenhouse gases in the atmosphere and might one day be useful for cleaning up oil spills.
Researchers documented extensive diversity in the microbial communities living in the extremely hot, deep-sea sediments located in the Guaymas Basin in the Gulf of California.
The team uncovered new microbial species that are so genetically different from those that have been previously studied that they represent new branches in the tree of life
Many of these same species possess keen pollutant-eating powers, like other, previously identified microbes in the ocean and soil.
The new study represented the largest-ever genomic sampling of Guaymas Basin sediments. The researchers' analysis of sediment from 2,000 meters below the surface, where volcanic activity raises temperatures to around 200 degrees Celsius, recovered 551 genomes, 22 of which represented new entries in the tree of life. According to the researchers, these new species were genetically different enough to represent new branches in the tree of life, and some were different enough to represent entirely new phyla.
Only about 0.1 percent of the world's microbes can be cultured, which means there are thousands, maybe even millions, of microbes yet to be discovered.
The team investigates interactions between microbial communities and the nutrients available to them in the environment by taking samples of sediment and microbes in nature, and then extracting DNA from the samples. The researchers sequence the DNA to piece together individual genomes, the sets of genes in each organism, and infer from the data how microbes consume different nutrients.
The samples were collected using the Alvin submersible, the same sub that found the Titanic, because the microbes live in extreme environments. This research was supported by the U.S. Department of Energy, the Sloan Foundation and the U.S. National Science Foundation.