Conjugal Transfer of Antibiotic Resistances in Lactobacillus spp.

Lactic acid bacteria (LAB) are a heterogeneous group of bacteria which are Gram-positive, facultative anaerobes and non-motile, non-spore forming, with varied shapes from cocci to coccobacilli and bacilli. Lactobacillus is the largest and most widely used bacterial species amongst LAB in fermented foods and beverages. The genus is a common member of human gut microbiome. Several species are known to provide benefits to the human gut via synergistic interactions with the gut microbiome and their ability to survive the gut environment. This ability to confer positive health effects provide them a status of generally recognized as safe (GRAS) microorganisms. Due to their various beneficial characteristics, other factors such as their resistance acquisition were overlooked. Overuse of antibiotics has made certain bacteria develop resistance against these drugs. Antibiotic resistance was found to be acquired mainly through conjugation which is a type of lateral gene transfer. Several in vitro methods of conjugation have been discussed previously depending on their success to transfer resistance. In this review, we have addressed methods that are employed to study the transfer of resistance genes using the conjugation phenomenon in lactobacilli.