Bioengineering a Probiotic to Bloom During Colonic Inflammation Promotes Reliable Efficacy in Translational Models of Colitis.

Bioengineering Escherichia coli Nissle 1917 with the ttr operon enables effective treatment of colitis by promoting colonization during inflammation, outperforming traditional therapies.

• Why it matters: Current microbial treatments for inflammatory bowel disease (IBD) lack consistent clinical efficacy, partly due to their inability to persist in the inflamed gut environment, limiting therapeutic potential.
• What they did: The researchers introduced the ttr operon into EcN to create EcN::ttr, which uses tetrathionate as fuel, and tested its efficacy in murine colitis models, including IL10-deficient mice and human colonoids, to assess its therapeutic impact.
• The result: EcN::ttr significantly improved colitis outcomes by enhancing immunoregulatory responses, promoting mucosal healing, and modifying the microbiome, demonstrating its potential as a robust microbiome-based therapy for IBD.