The National Institutes of Health estimate that about 90 percent of infections in humans are caused by biofilms, and the Centers for Disease Control estimate biofilm to be present in 65 percent of hospital-acquired (nosocomial) infections. Biofilms typically are the cause of fatal infections that develop post surgery. More commonly, they are the source of persistent ear infections among children.

In addition to finding that biofilm formation relies heavily on virus genes present within the bacteria, Wood's research has shown the mechanism for how this takes place. A protein within the bacterium called Hha has the ability to control whether virus genes are kept within the bacterium or jettisoned. When Hha is basically "turned on," the bacteria expel the virus genes, opting for motility over the ability to form biofilms. Likewise, when Hha is not expressed, the bacteria move slower but grow biofilms at a much faster rate, Wood explains.

It's a finding that could impact everything from health care to research into alternative fuel production.

"If we can understand how biofilms are formed, we can begin to manipulate forming them where we want and getting them to not form where we don't want them," Wood says. "We have found a regulator - this Hha - that controls the genes related to biofilm formation. Now we can begin to envision ways to turn on that Hha gene if we want to get rid of biofilms, and that is what we are working on. That's the long-term goal - as engineers to make biofilms where we want them.

"For example, if we want to remediate soil, we'd form a biofilm on the roots of plants, plant the tree, and wherever the tree root goes we clean the soil. That's a beneficial biofilm. If I want to make hydrogen with E. coli, I'll probably want to do it in a biofilm, so I would want to promote the growth of the biofilm.

"We're one of the first labs in the world that has begun to not only try to understand how biofilms form but to control them."

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