摘要
以从患羔羊痢疾的羔羊粪便中分离的1株大肠杆菌为宿主菌,从污水中分离纯化1株烈性大肠杆菌特异性噬菌体φPTK,并对其生物学特性进行研究,为研制一种替代抗生素的有效生物防治方法提供资源。双层琼脂平板培养后,噬菌斑呈现清晰透明、边缘光滑的圆形,直径2~3 mm。噬菌体φPTK生物学特性试验结果表明:φPTK对大肠杆菌的最佳感染复数为0.000 1;φPTK吸附和感染宿主菌的潜伏期为15 min,裂解期约195 min,裂解量93;噬菌体浓缩液经SDS-PAGE分析可以观察到至少6条蛋白质条带,相对分子质量为2.5×10~4~1.8×10~5,说明其蛋白质外壳至少含有6个结构蛋白;在30~90℃范围内φPTK的裂解活性均较强,30~40℃时活性最高,90℃处理90 min后仍然具有较强的活性;对酸碱的耐受力较强,p H值在5至9范围内均有较强的裂解活性,当p H值超过9后活性较低;对紫外线的耐受能力较强,经紫外线照射8 h后仍然具有较强的裂解能力。这株烈性大肠杆菌特异性噬菌体φPTK最佳感染复数较小,吸附和感染宿主菌的潜伏期短,裂解能力强,杀菌效果好,有较强的环境适应能力,具有研发成为有效防治羔羊大肠杆菌病的生物杀菌制剂的潜力。
In order to provide an alternative antibiotics for the prevention of lamb dysentery,a lamb-associated Escherichia coli virulent specific bacteriophage,named φPTK,was isolated and purified from sewage,and its biological characteristics were determined. The plaque of the phage φPTK showed circular,clear and transparent with smooth edge,showing 2-3 mm of diameter,using the double-layer agar plate method. The analysis results of its biological properties showed that the optimal multiplicity of infection（ MOI） was 0.000 1. The determination of one-step growth kinetics showed a short latency period of about 15 min and a burst phase time of 195 min and a relatively larger burst size was 93. The structural proteome of phage φPTK was analyzed by SDS-PAGE,at least six protein bands could be observed with a relative molecular mass of 2.5×10^4-1.8×10^5,indicating that the phage φPTK had at least six structural proteins. In the range of 30-90 ℃,φPTK had a strong lytic activity,and the activity was highest at 30-40 ℃. After treated 90 minutes at 90 ℃,it still had a strong activity. Phage φPTK was quite stable in a wide range of p H values（ p H 5-9）. Moreover,phageφPTK was resistant to ultraviolet ray treatment,and the titer was still remained a high level after ultraviolet irradia-tion for eight hours. In the present study,an E. coli-specific virulent phage was isolated,the phage φPTK had a short latency period,strong lytic activity and ability of sterilization. It has the potential to be developed as a new approach to control the lamb-associated E. coli disease.
作者
李陇平
杨吉
白蹉蹉
杨悦
屈雷
LI Long-ping;YANG Ji;BAI Cuo-cuo;YANG Yuc;QU Lei(ShaaTeci Provincial Engineering and Technology Research Center of Cashmere Goats,Yulin University,Yulin 719000,China)
出处
《江苏农业学报》
CSCD
北大核心
2018年第4期847-853,共7页
Jiangsu Journal of Agricultural Sciences
基金
陕西省高校科协青年人才托举计划项目(20160236)
榆林学院高层次人才科研启动基金项目(16GK21)
关键词
绒山羊
羔羊痢疾
大肠杆菌
噬菌体
生物学特性
cashmere goat
diarrhoea
Escherichia coli
bacteriophage
biological properties
