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KNOXVILLE— A pathogen that attacks the small intestines of humans and animals is serving as the inspiration for developing robots that can fight disease and aid in military operations.

Mingjun Zhang, associate professor in mechanical, aerospace and biomedical engineering, at the University of Tennessee, Knoxville, and his team have made significant findings about the swimming and attachment of the microorganism Giardia. Giardia causes one of the most common gastrointestinal diseases in the world, giardiasis. For 250 years, scientists have tried to understand how the microorganism is able to attach to a multitude of surfaces and swim in harsh environments—enabling it to infect many kinds of species while most parasites have specific hosts. Zhang and his team have made significant progress to solve the puzzle.

Giardia lamblia protozoan parasite.
Giardia lamblia protozoan parasite. Photo courtesy of the Centers for Disease Control and Prevention.

“We found each of the four pairs of flagella conducts different functions,” Zhang said of some of the team’s findings. “This is amazing considering the length of the flagella is only about eight to twelve micrometers each, with a diameter of a few hundred nanometers.”

The team’s discovery can aid in fighting the pathogen’s attack and others like it. The discovery may help to develop a way to block its attachment in the human intestine as an alternative for treating the disease. The discovery may also lead to bio-inspired swimming micro-robots for nanomedicine, such as site-specific controlled drug delivery and less invasive surgical procedures. For instance, micro-robots can navigate through the body to break up kidney stones, deliver drugs to specific sites after injection and reduce the invasiveness of surgery.

On a larger scale, knowing Giardia‘s inner workings may buoy an energy-efficient propulsion system for underwater vehicles or designs for quick turn and agile control of underwater vehicles. The findings of Giardia‘s unique attachment and landing procedures may also inspire a more accurate and quick surface attachment mechanism.

Giardia seems to be one of the most sophisticated swimming microorganisms and is very efficient and intelligent in terms of controlling its swimming behavior and energy utilization,” Zhang said. “It is a source rife with bio-inspiration and innovation.”

Zhang conducted this study with Scott Lenaghan, a post-doctoral research associate; Zhili Zhang, assistant professor in the department of Mechanical, Aerospace and Biomedical Engineering, and Corinne Davis and William Henson, Chancellor’s honors students in the department of Mechanical, Aerospace and Biomedical Engineering.

Their findings are published in the current edition of the Proceedings of the National Academy of Sciences.

The research is being funded by the Office of Naval Research 2011 Young Investigator Program. UT was one of only two universities to have two professors receive the award this year. The award gives Zhang $170,000 in annual research grants every year for three years.

C O N T A C T :

Whitney Holmes (865-974-5460,

Mingjun Zhang (865-974-7620,