Horizontal gene transfer mediated bacterial antibiotic resistance

Bacterial antibiotic resistance, especially multidrug resistance (MDR), has become a global challenge, threatening human and animal health, food and environment safety. The number of human deaths accounted for by multidrug resistance (MDR) was estimated to increase to 10 million by 2050, exceeding the number of deaths arising from cancer (WHO, 2014). Although a bacterium is able to establish antibiotic resistance through spontaneous mutation (Salverda et al., 2017), development of MDR in the bacterium would take a long time if it only relies on self-adaptive mutation. Horizontal gene transfer (HGT) allows bacteria to exchange their genetic materials (including antibiotic resistance genes, ARGs) among diverse species (Le Roux and Blokesch, 2018), greatly fostering collaboration among bacterial population in MDR development. Recent studies reveal emergence of ‘superbugs’ that carry a number of HGT-transferred ARGs on plasmids and tolerate almost all antibiotics (Mathers et al., 2015; Wang and Sun, 2015; Malhotra-Kumar et al., 2016). These MDR plasmids are able to be further transferred to different bacterial species, creating new ‘superbugs’ that grow in different environments. Global emergence of ‘superbugs’ carrying MDR plasmids (e. g. NDM-1 and MCR-1) in various environmental niches (e. g. patients, animals and soil) indicates rapid propagation of MDR among bacterial populations. Although HGT and MDR were found to be tightly linked in ‘superbugs’, as revealed by surveillance studies, our knowledge about how and to what extend HGT propels development of MDR under different environmental conditions remain inadequate. The 22 publications collected in the topic “Horizontal Gene Transfer Mediated Bacterial Antibiotic Resistance” show new discoveries and recent advances concerning this issue in a wide range of fields, providing a basis for collaboratively controlling MDR in the future.