Factors influencing horizontal gene transfer in the intestine

Abstract

AbstractAntibiotic resistance (AR) is ancient. Use of antibiotics is a selective driving force that enriches AR genes and promotes the emergence of resistant pathogens. It also has been widely accepted that horizontal gene transfer (HGT) occurs everywhere and plays a critical role in the transmission of AR genes among bacteria. However, our understanding of HGT processes primarily build on extensivein vitrostudies; to date, there is still a significant knowledge gap regardingin situHGT events as well as the factors that influence HGT in different ecological niches. This review is focused on the HGT process in the intestinal tract, a ‘melting pot’ for gene exchange. Several factors that potentially influencein vivoHGT efficiency in the intestine are identified and summarized, which include SOS-inducing agents, stress hormones, microbiota and microbiota-derived factors. We highlight recent discoveries demonstrating that certain antibiotics, which are widely used in animal industry, can enhance HGT in the intestine by serving as DNA-damaging, SOS-inducing agents. Despite recent progress, research onin vivoHGT events is still in its infancy. A better understanding of the factors influencing HGT in the intestine is highly warranted for developing effective strategies to mitigate AR in animal production as well as in future agricultural ecosystems.