University of Colorado at Boulder researchers have discovered four new kingdoms of life in the high alpine environment of Colorado, findings that have potential applications in the fields of agriculture and global change.
Doctoral student Allen Meyer and Professor Steven Schmidt of the environmental, population and organismic biology department discovered the new microbe kingdoms in barren, boulder-filled tundra slopes west of Boulder.
At altitudes of 11,000 feet to 13,000 feet in elevation just east of the Continental Divide, the region receives nine months of snow and three months of intense sun and wind, said Meyer.
Although scientists in the 18th century originally classified the kingdoms of life into two groups -- plants and animals -- many scientists now believe there are many more, including fungi and a number of types of single-celled organisms. Because of new scientific tools resulting in sophisticated DNA analysis, the number of kingdoms was estimated to be about 30 before the CU-Boulder findings, said Meyer.
Funded by the National Science Foundation's program, "Microbial Observatories," the findings will be presented at the 103rd General Meeting of the American Society for Microbiology in Washington, D.C., by Allen on May 19.
Meyer and Schmidt used a novel molecular technique that extracts DNA from the soil to identify the organisms living there. "The discovery of new kingdoms means more undiscovered species exist," said Meyer.
The researchers concentrated their research on eukaryotic microbes -- microscopic organisms that have a membrane around their DNA. The number of microbe species has been growing as scientists use new DNA techniques to uncover the family of eukaryotes, they said.
Unearthing new organisms might even help in solving practical problems in agriculture and ecology, Meyer said. "Newly discovered microbial eukaryotes could be of benefit in understanding soil diversity that may be important in predicting impacts of global change, for example."
In addition, newly discovered eukaryotes could potentially be of benefit in newer sewage treatment plants to help other microbes convert nitrates from agricultural pollution into harmless nitrogen and oxygen, he said. The CU-Boulder researchers might even be able to find new microbes to fight off disease in plants.
"These family trees, or phylogenies, help scientists group organisms into kingdoms," said Meyer. The most important of these approaches involves the small, sub-unit ribosomal gene, key for making proteins."
Instead of culturing organisms, Meyer and Schmidt extracted DNA directly from the soil, obtaining DNA from all the soil organisms at once. Comparing their gene sequencing results with those of known eukaryote organisms allowed them to discover the sequences from the four new kingdoms.
Although they have the sequences of four previously unknown kingdoms, they have not yet identified the specific organisms themselves, said Schmidt. "But now that we know these microbes are in the alpine soil, we can go back and isolate them in these extreme environments and study them.
"We will be using PCR, or polymerase chain reaction, to amplify and identify organisms to get a snapshot of the diversity of soil-organism diversity in the high alpine," said Schmidt.
"Another important issue is that our alpine regions are changing rapidly, said Schmidt. "Depending on the pattern of decreasing snow cover over the past several years, we are racing to identify the species before bigger changes occur and some of the species disappear before they can be identified."