新广谱大肠杆菌噬菌体IME11的分离及鉴定

目的 分离广谱大肠杆菌噬菌体并对其进行种属的鉴定。方法 以不同种临床致病性大肠杆菌为指示菌，从未经处理的污水样品中分离噬菌体；采用蛋白酶K/SDS的方法提取噬菌体基因组，制备重组载体，将阳性重组质粒进行测序；将测序结果进行BLAST，推测该噬菌体种属分类位置。结果 分别以大肠杆菌E1 ～ E17共17种细菌作为指示菌，成功分离出一种广谱噬菌体，可裂解31株临床分离致病性大肠杆菌中的13株，并将其命名为IME11；由噬菌体基因组限制性酶切片段分析表明其遗传物质为dsDNA；将噬菌体IME11基因组的2个随机片段测序结果进行BLAST，推测其属于N4-like噬菌体属。结论 分离出了一种广谱噬菌体，在分类学上属于N4-like噬菌体属。

Isolation and classification of new broad spectrum Escherichia coli bacteriophage IMEll

Objective To isolate and classify the bacteriophages and identify their species. Methods With different Escherichia coli clinical strains as indicators, the bacteriophages were isolated by screening untreated sewage samples, and the phage genomic DNA was extracted by proteinase K/SDS methods. The recombinant vector and positive clones were selected and sequenced. The NCBI＇s nucleotide BLAST program（BLASTN） was used to study sequencing result matches. Results With Escherichia coli E 1 - El7 as indicators, broad-spectrum bacteriophage named IME11 was successfully isolated. Accorded to the result of restriction fragment analysis,its genetic material was dsDNA. The BLAST sequencing results of 2 random fragments from IME 11 indicated that it belonged to the genus ＂N4-1ike viruses＂. Conclusion It is demonstrated that the isolated new broad-spectrum bacteriophage belongs to the ＂N4-1ike viruses＂.