Million-year-old bacteria in the Arctic Circle of Siberia and organisms that destroy hazardous waste are just two of the subjects of study in the National Science Foundation Center for Microbial Ecology (CME) at MSU. "Half of the living protoplasm on our planet is microbial, and yet we know less than one percent of it," says Jim Tiedje, the center's director. "Discovering the unknown microbial world is our biggest opportunity for the future."

Microbiologist Bob Hausinger studies microbial enzymes that decompose synthetic chemicals and naturally occurring compounds - research that may benefit both agriculture and medicine. As an example, he studies urease, used by plants and many soil microbes to break down urea for its nitrogen, an element essential to the life cycle of all organisms. In humans, urease is also associated with the formation of urinary stones, peptic ulcers, and possibly stomach cancer.

A surprising feature of urease is that it requires nickel; it is the first enzyme shown to contain this metal. Hausinger and his colleagues have determined the first complete three-dimensional structure of urease, characterized how it functions, and defined steps in its selective incorporation of nickel. "We're at a pivotal stage in this research," says Hausinger. "Knowing how to prevent the metal center from forming may be the key to inhibiting and controlling urease activity."