NC: 抗性基因的传播
Abstract: It has been hypothesized that some antibiotic resistance genes (ARGs) found in pathogenic bacteria derive from antibiotic-producing actinobacteria. Here we provide bioinformatic and experimental evidence supporting this hypothesis. We identify genes in proteobacteria, including some pathogens, that appear to be closely related to actinobacterial ARGs known to confer resistance against clinically important antibiotics. Furthermore, we identify two potential examples of recent horizontal transfer of actinobacterial ARGs to proteobacterial pathogens. Based on this bioinformatic evidence, we propose and experimentally test a ‘carry-back’ mechanism for the transfer, involving conjugative transfer of a carrier sequence from proteobacteria to actinobacteria, recombination of the carrier sequence with the actinobacterial ARG, followed by natural transformation of proteobacteria with the carrier-sandwiched ARG. Our results support the existence of ancient and, possibly, recent transfers of ARGs from antibiotic-producing actinobacteria to proteobacteria, and provide evidence for a defined mechanism.
中文摘要：据推测，在致病菌中发现的一些抗生素抗性基因（ARG）来源于产生抗生素的放线菌。这里我们提供支持这个假设的生物信息学和实验证据。我们确定变形杆菌中的基因，包括一些病原体，这些基因似乎与已知赋予临床重要抗生素抗性的放线菌ARG密切相关。此外，我们确定了最近将放线菌ARGs水平转移到变形杆菌病原体的两个潜在的例子。基于这种生物信息学证据，我们提出并实验性地测试了转移的“回传”机制，涉及载体序列从变形杆菌到放线菌的共轭转移，载体序列与放线菌ARG的重组，随后自然转化变形杆菌与载体夹心ARG。我们的研究结果支持ARGs从抗生素产生的放线菌到变形杆菌的古老和可能最近的转移的存在，并为确定的机制提供证据。（Google翻译，未整理，供参考）
DOI: 10.1038/ncomms15784
