摘要

对抗生素的抗药性可能是微生物的正常进化过程，但是由于广泛和滥用抗菌药物而加速了抗生素的应用。已知编码扩展谱β内酰胺酶的质粒基因型blaCTX-M-15在大肠杆菌分离株中普遍存在。移动遗传因子，如介导水平基因转移的质粒，转座子，整合子和噬菌体等，是抗生素抗性基因传播最多的因素。使用对β内酰胺敏感的细菌宿主作为诱饵，从印度Mangaluru市污水排放口抽取的15个样品中分离出大肠杆菌特异性噬菌体。在分离的36个噬菌体中，7个对blaCTX-M-15呈阳性。据我们所知，这是第一次分离含有抗性基因blaCTX-M-15的特定噬菌体的报道。该基因在噬菌体DNA库中的高发病率（20％）证实了噬菌体在传播抗性基因中的关键作用。

Resistance to antibiotics can be a normal evolutionary process for microorganisms, but is accelerated by the widespread and indiscriminate use of antibacterial drugs. The plasmid genotype blaCTX-M-15 which encodes for an extended spectrum β lactamase is known to be prevalent in Escherichia coli isolates. Mobile genetic elements such as plasmids, transposons, integrons and bacteriophages mediating horizontal gene transfer are the most involved in the spread of antibiotic-resistance genes. E. coli specific bacteriophages were isolated from 15 samples drawn from sewage outfalls across Mangaluru city, India using bacterial hosts that were sensitive to βlactams as baits. Of 36 phages isolated, 7 were positive for blaCTX-M-15. To our knowledge, this is the first report of isolation of specific bacteriophages harboring the resistance gene blaCTX-M-15. The high prevalence (20%) of this gene in the phage DNA pool confirms the pivotal role of bacteriophages in the dissemination of resistance genes.

http://www.ingentaconnect.com/content/asp/asl/2017/00000023/00000003/art00084