(Blacksburg, Va., Sept. 27, 1999) -- Microbial interactions with mineral surfaces influence the bioavailability of both nutrients and contaminants in the environment, impacting such diverse environmental processes as the fate and transport of heavy metals, biodegradation of environmental contaminants, and effective use of agrochemicals. Yet, as critical as microbe-mineral interactions are, in terms of research, "minerals and microbes might as well be night and day," says Virginia Tech geochemist Michael Hochella.
"We know that the earth communicates with water and air, that microorganisms alter the physical and chemical properties of minerals, and that the diversity and distribution of microorganism on earth is at least in part due to the dynamic geochemistry of mineral surfaces," says Hochella. "Thousands of minerals with enormous variability in surface chemistry and structure interact with any of an unimaginable number of microbial species; yet, despite the vast amount of work in geochemistry and microbiology, microbe-mineral interactions remain largely unexplored."
He decided to change that and in 1996 launched the university's Microbe-Mineral Group with microbial ecologist Duane Berry and environmental engineer John Little.
After three years of weekly meetings to learn each other's science, study of a model microbe-mineral interaction, and cross-training of graduate students, the Virginia Tech group has received a three-year, $386,202 grant from the Department of Energy, effective Sept. 15, 1999.
"The intent is to discover and define the conditions under which
microbes cause the release of nutrients or contaminants from mineral surfaces,"
says Hochella. The model the researchers are studying are microbes that, in a
glucose environment, release phosphorous from goethite -- the most common iron
oxide in soils worldwide. In the glucose environment, microbes alter their
metabolism to produce glucolipids, and even reduce their cell size,
Contact: Michael F. Hochella Jr.