Synthetic biologists at Rice University have genetically engineered bacteria to sense inflammation associated with colitis in the gut. Currently, expensive and invasive colonoscopy procedures are required to assess gut health. Swallowing a bacterial sensor that can report on gut health could help patients with inflammatory gut illness to avoid these.
The team hypothesized that a molecule called thiosulfate is increased in the inflamed gut. They identified genes encoding for sulfate sensors in bacteria that live in marine sediment. By genetically modifying E. coli to express the genes, the researchers created a bacterium that could produce a green fluorescent protein in the presence of thiosulfate.
The bacteria were administered orally to healthy mice or mice with colitis. Mice with colitis showed the green fluorescent protein in their feces, providing a positive diagnosis without the need for invasive procedures. The researchers were also able to correlate the amount of green fluorescent protein with inflammation severity in each mouse, meaning that the sensor could quantify disease severity.
It remains to be seen whether thiosulfate is a biomarker for human colitis, but the team have plans to develop the therapy for human patients. “We’d like to develop a home inflammation test where a person prone to colitis flare-ups would eat yogurt that contained the engineered bacteria and see blue pigment in the toilet if they were sick,” said corresponding author on the study, Jeffrey Tabor.
Study in Molecular Systems Biology: Engineering bacterial thiosulfate and tetrathionate sensors for detecting gut inflammation…
Via: Rice…
