• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Frontiers in Public Health >Characterization of Lytic Bacteriophages Infecting Multidrug-Resistant Shiga Toxigenic Atypical Escherichia coli O177 Strains Isolated From Cattle Feces
【24h】

Characterization of Lytic Bacteriophages Infecting Multidrug-Resistant Shiga Toxigenic Atypical Escherichia coli O177 Strains Isolated From Cattle Feces

机译：感染裂解血清毒性多典型大肠杆菌O177从牛粪中分离的裂解性噬菌体的表征

获取原文
       
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

The increasing incidence of antibiotic resistance and emergence of virulent bacterial pathogens, coupled with a lack of new effective antibiotics, has reignited interest in the use of lytic bacteriophage therapy. The aim of this study was to characterize lytic Escherichia coli O177-specific bacteriophages isolated from cattle feces to determine their potential application as biocontrol agents. A total of 31 lytic E. coli O177-specific bacteriophages were isolated. A large proportion (71%) of these phage isolates produced large plaques while 29% produced small plaques on 0.3% soft agar. Based on different plaque morphologies and clarity and size of plaques, eight phages were selected for further analyses. Spot test and efficiency of plating (EOP) analyses were performed to determine the host range for selected phages. Phage morphotype and growth were analyzed using transmission electron microscopy and the one-step growth curve method. Phages were also assessed for thermal and pH stability. The spot test revealed that all selected phages were capable of infecting different environmental E. coli strains. However, none of the phages infected American Type Culture Collection (ATCC) and environmental Salmonella strains. Furthermore, EOP analysis (range: 0.1–1.0) showed that phages were capable of infecting a wide range of E. coli isolates. Selected phage isolates had a similar morphotype (an icosahedral head and a contractile tail) and were classified under the order Caudovirales, Myoviridae family. The icosahedral heads ranged from 81.2 to 110.77 nm, while the contractile tails ranged from 115.55 to 132.57 nm in size. The phages were found to be still active after 60 min of incubation at 37 and 40°C. Incremental levels of pH induced a quadratic response on stability of all phages. The pH optima for all eight phages ranged between 7.6 and 8.0, while at pH 3.0 all phages were inactive. Phage latent period ranged between 15 and 25 min while burst size ranged from 91 to 522 virion particles [plaque-forming unit (PFU)] per infected cell. These results demonstrate that lytic E. coli O177-specific bacteriophages isolated from cattle feces are highly stable and have the capacity to infect different E. coli strains, traits that make them potential biocontrol agents.
机译：抗生素抗性发病率越来越多，致毒性细菌病原体的出现，同时缺乏新的有效抗生素，对使用裂解性噬菌体治疗的兴趣令人兴趣。本研究的目的是表征从牛粪中分离的裂解性大肠杆菌O177特异性噬菌体，以确定其作为生物控制剂的潜在应用。分离了总共31种裂解大肠杆菌O177特异性噬菌体。大量（71％）这些噬菌体分离物产生大斑块，而29％在0.3％软琼脂上产生小斑块。基于不同的斑块形态和斑块的清晰度和尺寸，选择了八个噬菌体进行进一步分析。进行镀层（EOP）分析的现货测试和效率以确定所选噬菌体的主体范围。使用透射电子显微镜和一步生长曲线法分析噬菌体Mor晶型和生长。还评估了热和pH稳定性的噬菌体。现场试验显示，所有选定的噬菌体都能够感染不同的环境大肠杆菌菌株。然而，噬菌体都没有感染美国培养物收集（ATCC）和环境沙门氏菌菌株。此外，EOP分析（范围：0.1-1.0）显示噬菌体能够感染各种大肠杆菌分离株。选定的噬菌体分离物具有类似的Mor晶型（IcosaheDral头部和收缩尾部），并在Caudovirales，Myoviridae家族命令下进行分类。 ICOSAHEDRAL头部的81.2至110.77 nm，而收缩尾部的尺寸为115.55至132.57纳米。在37和40℃温育60分钟后，发现噬菌体仍然活跃。 pH值的增量水平诱导所有噬菌体稳定性的二次反应。所有八个噬菌体的pH值范围为7.6和8.0，而在pH 3.0时，所有噬菌体都无效。噬菌体潜伏期在15到25分钟之间，而突发尺寸范围为91至522天病毒粒粒子（斑块形成单位（PFU）]，每个受感染的细胞。这些结果表明，从牛粪中分离的裂解大肠杆菌O177特异性噬菌体是高度稳定的并且具有感染不同大肠杆菌菌株的能力，使其成为潜在的生物控制剂的特征。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号