SAN JOSE, Calif. – A Stanford-designed project has built a startling new tool for diagnostic medicine: Living biosensors made of bacteria that glow a particular color when they detect trouble.

The team rewired the genetic circuitry inside bacterial cells so that the cells recognized abnormal glucose levels in urine, signaling diabetes.

The custom-designed bacteria show the practical promise of the fledgling field of synthetic biology, which designs and builds organisms unlike anything made by Mother Nature.

"We are showing that we can begin to use engineering tools to systematically program cells for use as human medical diagnostics," said Drew Endy of Stanford's School of Engineering, where the project had its start before moving with its lead investigator Jerome Bonnet to France's Institut de Genetique Moleculaire de Montpellier.

The cells, tested in patients' urine samples, performed almost as well as the conventional diabetes dipstick, Bonnet reported.

While there are still technical hurdles to be overcome, bacterial biosensors could be faster, cheaper and more durable than traditional tests, Bonnet reported in the journal Science Translational Medicine.

This approach could aid earlier detection of upward or downward swings of blood glucose levels, said Dr. Samuel Dagogo-Jack, president of medicine and science for the American Diabetes Association.

San Jose Mercury News