水平基因转移介导抗菌素耐药性传播机制的研究进展

近几十年来,病原菌耐药性的出现和蔓延已上升为严峻的公共卫生问题。越来越多研究表明,抗菌素抗性基因(antibiotic resistance genes,ARGs)不仅仅见于临床所分离的病原体,而是包括所有的致病菌、共生菌以及环境中的细菌,它们都能在可移动遗传元件和噬菌体的作用下,通过水平基因转移(horizontal gene transfer,HGT)途径获得耐药性,进而形成抗菌素耐药基因簇(耐药基因组)。HGT可导致抗菌素的耐药性在环境共生菌和病原菌之间传播扩散,这可通过临床上一些重要的抗菌素耐药基因的传播证实。传统观念认为HGT的三种机制中,接合对ARGs的传播影响最大,最近研究表明转化和转导对ARGs播散起到不可忽视的作用。通过深入了解耐药基因组的传播及其在动员病原菌耐药中发挥的作用,对于控制这些基因的播散是至关重要的。将讨论耐药基因组的概念,提供临床相关的抗菌素抗性基因水平基因转移的例子,对当前已研究的促使抗菌素耐药性传播的各种HGT机制进行回顾。

Dissemination of Antimicrobial Resistance through Horizontal Gene Transfer

In recent decades, the emergence and spread of antibiotic resistance among pathogenic bacteria has been a rising problem of graveness for public health. More and more studies suggested that antibiotic resistance genes (ARGs) were not only encountered in clinical isolated pathogens, but all of the pathogenic bacteria, symbiotic bacteria, as well as the environment of bacteria. Under the action of the mobile genetic elements and bacteriophages, all of them were able to obtain drug resistance via the horizontal gene transfer (HGT) and then proceeded to form antibiotics resistance genes (ARG) cluster (medicine resistance genome). HGT could cause antibiotic resistance to spread among commensal bacteria in environment and pathogens, as has been proven through the spread of some clinically important ARGs. Traditional sense considered that among the three mechanisms of HGT, conjugation was thought to have the greatest influence on the spread of ARGs. And recent studies suggested that metaplasia and transduction were deemed to play a position in the dissemination of ARGs that could not be ignored.Thorough understanding the spread of the ARG and its role played in the mobilization of pathogen resistance is the most important to control the spread of these genes. Here, the concept of ARG will be discussed to provide examples of HGT of clinically related ARGs and present an overview of the current studies that have been carried out on the spread of ARGs of various HGT mechanisms that hasten to the spread of ARGs.