In a recent study published in Nature, scientists from the Shanghai Academy of Natural Sciences (SANS) in China developed an oral living drug, GIFT, made from engineered probiotic bacteria. The bacteria carry a built-in molecular glucose sensor, created using a gene circuit controlled by a sensor protein called HexR.

Once swallowed, the probiotics temporarily reside in the intestine. When the sensor detects blood sugar rising above normal levels, it switches on therapeutic genes in the bacteria that produce and release GLP-1, a hormone that triggers insulin release to lower blood sugar.