Microbes can be genetically modified to express biomolecules that are beneficial to mammals and/or to reduce, or eliminate, expression of harmful virulence factors. The growth and viability of such genetically modified microbes can optionally be controlled by inducible promoters that regulate the expression of proteins that are essential to their growth and survival. Compositions comprising such genetically modified microbes as well as methods of making and using the same are disclosed herein.
