Author information

1 Fischell Dept. of Bioengineering University of Maryland College Park MD.

2 Institute for Bioscience and Biotechnology Research University of Maryland College Park MD.

3 Women's Malignancies Branch, Center for Cancer Research, National Cancer Institute National Institutes of Health Bethesda MD.

4 Marlene and Stewart Greenebaum Comprehensive Cancer Center University of Maryland School of Medicine Baltimore MD.

5 Program in Molecular and Cellular Biology University of Maryland College Park MD.

6 Dept. of Biochemistry, Yong Loo Lin School of Medicine National University of Singapore Singapore.

7 NUS Synthetic Biology for Clinical and Technological Innovation, Life Sciences Institute National University of Singapore Singapore.

8 Dept. of Biological and Environmental Engineering Cornell University Ithaca NY.

Abstract

For therapies targeting diseases of the gastrointestinal tract, we and others envision probiotic bacteria that synthesize and excrete biotherapeutics at disease sites. Toward this goal, we have engineered commensal E. coli that selectively synthesize and secrete a model biotherapeutic in the presence of nitric oxide (NO), an intestinal biomarker for Crohn's disease (CD). This is accomplished by co-expressing the pore forming protein TolAIII with the biologic, granulocyte macrophage-colony stimulating factor (GM-CSF). We have additionally engineered these bacteria to accumulate at sites of elevated NO by engineering their motility circuits and controlling pseudotaxis. Importantly, because we have focused on in vitro test beds, motility and biotherapeutics production are spatiotemporally characterized. Together, the targeted recognition, synthesis, and biomolecule delivery comprises a "smart" probiotics platform that may have utility in the treatment of CD. Further, this platform could be modified to accommodate other pursuits by swapping the promoter and therapeutic gene to reflect other disease biomarkers and treatments, respectively.