**Abstract**

Although natural gut microbiota contains *Escherichia coli* as a commensal, this bacterium, along with other members of the *Enterobacteriaceae* family, are usually known for their pathogenic potential. Interestingly, *E. coli* colonizes first and remains all through life, and in fact, some strains possess beneficial properties such as antibacterial colicin secretion. Among the beneficial strains, *E. coli* Nissle, isolated in 1917, has been the most extensively explored strain. Adaptability to survive under diverse conditions coupled with facile genetic manipulations enabled the design of *E. coli* strains with properties to deliver antioxidant, anti-inflammatory, and antitumor molecules. Moreover, genetically modified *E. coli* strains secreting enzymes for converting sucrose and fructose into insulin and mannitol, respectively, were very effective in preventing the onset of metabolic disease by acting as synbiotics. Thus, *E. coli* is emerging as a very potent probiotic platform for developing strains with the potential of controlling many metabolic and multifactorial diseases, including cancer.

**Keywords:** *E. coli* Nissle, probiotic, prebiotic
