Tiedje, a University Distinguished Professor Emeritus in the MSU Department of Microbiology, Genetics and Immunologyand the Department of Plant, Soil and Microbial Sciences, discovered in this huge, unexplored microbial world a completely different phylum, or primary category, of microbe called CSP1-3. This new phylum was identified in soil samples from both Iowa and China at depths down to 70 feet. Why Iowa and China? Because these two areas have very deep and similar soils and we want to know if their occurrence is more general and not just in one area, Tiedje said.

Tiedje’s team extracted DNA from these deep soils and found that CSP1-3’s ancestors lived in the water — hot springs and fresh water — many millions of years ago. They underwent at least one major habitat transition to colonize soil environments — first topsoil and, later, deep soils, during its evolutionary history.

Tiedje also found that the microbes were active. “Most people would think that these organisms are just like spores or dormant,” he said. “But one of our key findings we found through examining their DNA is that these microbes are active and slowly growing.”