Editorial: Genetics of Acquired Antimicrobial Resistance in Animal and Zoonotic Pathogens

Antimicrobial resistance has become a global public health concern due to multidrug-resistant (MDR) bacteria and to the lack of novel antibiotics.Resistant bacteria, including zoonotic pathogens, can be exchanged between animals and humans through direct contact, the food chain, or contamination of the shared environment.Resistance to medically-important antibiotics such as extended spectrum beta-lactams, carbapenems, fluoroquinolones, or aminoglycosides, is of increasing magnitude among zoonotic pathogens.Acquired antimicrobial resistance is the result of an evolutionary process by which microorganisms adapt to antibiotics through several mechanisms including alteration of drug target by mutations and horizontal transfer of novel/foreign genes, referred to as resistance genes.Acquired resistance genes coding for any of the three major resistance mechanisms, i.e., enzymatic inactivation, reduced intracellular accumulation, or modification of the cellular target sites are associated with mobile genetic elements including plasmids, transposons, gene cassettes, integrative, and conjugative elements or other mobile elements (Schwarz et al., 2017).This Research Topic is focused on acquired antimicrobial resistance mechanisms in animal and zoonotic pathogens isolated from food-producing animals, food products, companion animals, humans, and the environment.Different sets of articles document the most important aspects of the genetics of acquired antimicrobial resistance extending from medically-important resistance genes such as those conferring resistance to extended spectrum cephalosporins and more recently those conferring resistance to colistin, emerging epidemic clones, primary mobile genetic elements such as class 1 integrons, culture-independent approach of resistomes, dissemination between animals and humans, to the "One Health" concept.First, in an elegant review article, Imperial and Ibana addressed the global problem of the spread of emerging antibiotic-resistant bacteria in the "One Health" perspective.They summarized the processes that govern the spread of antibiotic resistance in relation to resistance genes, their horizontal transfer through mobile genetic elements, the microbial ecology of resistant bacteria in the human gut microbiota, and their dissemination by international travel of humans, animals, or food.Finally, they discussed the probiotic use in both human and veterinary applications to tackle the antibiotic resistance threat and concluded on the "double-edged sword" with potential risk in propagating antibiotic resistance by probiotics.Salmonella enterica spp.are important zoonotic pathogens related to foodborne diseases worldwide.In the present Research Topic, Zhao et al. and Zhao et al. contributed with two research articles dealing with antimicrobial resistance of S. enterica serotypes isolated from food-producing animals (chickens, ducks, and pigs) in farms and slaughterhouses in the Shandong province, China.