The team has developed a probiotic using a genetically engineered version of E. coli Nissle, a harmless Gram-negative strain of bacteria found in the gut. Researchers at National University of…

The team has developed a probiotic using a genetically engineered version of E. coli Nissle, a harmless Gram-negative strain of bacteria found in the gut.

Researchers at National University of Singapore (NUS) have turned a humble cocktail of bacteria and vegetables into a targeted system that seeks out and kills colorectal cancer cells.  The team has developed a probiotic using a genetically engineered version of E. coli Nissle, a harmless Gram-negative strain of bacteria found in the gut. 

The mechanism of action of the engineered bacteria is to attach to a protein called heparan sulphate proteoglycan on colorectal cancer cells. The bacteria then secrete an enzyme that transforms a small molecule from broccoli (glucosinolates) into a potent anticancer agent (sulphoraphane). The bacteria do not bind to healthy cells, nor are the healthy cells affected by the toxin.

During their experiment, the researchers observed that the probiotics-broccoli extract reduced tumor volumes by 75 percent in mice with colorectal cancer.  The researchers envision that the probiotics cocktail could be used as a dietary supplement for preventive care, or to reduce tumor recurrence after surgery.