“We are looking to better understand the evolution of microbes in the groundwater plume,” Watson said. “The microbes that can break down nitrate into nitrogen can have a long-term benefit toward attenuating the plume.”

Microbes that live in contaminated groundwater.

(Image Credit: Image courtesy of DOE’s Oak Ridge National Laboratory)

Watson added that researchers particularly want to better understand the genetic makeup of microbes  that can  metabolize oxidized forms of uranium into a form that is only slightly soluble and thus easier to precipitate and remove from the groundwater environment.

ORNL's Watson was joined in the study by the University of Oklahoma's Jizhong Zhou and Christopher Hemme; Joint Genome Institute Director Eddy Rubin and a team that included researchers from ORNL's Environmental Sciences Division, the University of Oklahoma's Institute for Environmental Genomics, Montana State University, Michigan State University and Lawrence Berkeley National Laboratory.

They found that the naturally occurring populations of microbes in the polluted groundwater which consisted of only a few cell types had “very simple” genetic structures tuned primarily to overcoming the stresses presented by the toxic soup, which has a highly acidic pH level of 3.5.

The accumulation of genes involved in resistance and responses to stress appears to be a basic survival strategy that has left the microbes with a marked loss in metabolic diversity.

The waste ponds, which are now part of the Oak Ridge Environmental Remediation Sciences Program Integrated Field Research Center, have been out of use for decades and were capped in 1983.

The research, recently published in the on-line ISME (International Society for Microbial Ecology) Journal, is sponsored by DOE's Office of Science.

Source: www.sciencedaily.com