Horizontal gene transfer amongst probiotic lactic acid bacteria and other intestinal microbiota: what are the possibilities? A review.

Probiotics are live cultures, usually lactic acid bacteria, which are ingested to promote a healthy gastrointestinal tract. These organisms require certain traits to survive and compete in this niche, but these traits may be transferred to other microbiota in the gastrointestinal tract (GIT). Similarly, virulence factors from pathogens may be acquired by probiotic strains. Bacteria have developed a plethora of methods to transfer genetic material between strains, species and genera. In this review, the possible factors that may be exchanged and the methods of exchange are discussed.