一株假单胞菌属低温噬菌体的分离及其特性研究  

Isolation and characterization of a Pseudomonas-specific cold-active bacteriophage

作　　者：崔尹赡[1] 易萍[1] 许忠福[1] 魏云林[1] 张琦[1] 林连兵[1] 季秀玲[1] 

机构地区：[1]昆明理工大学生命科学与技术学院,云南昆明650500

出　　处：《中国微生态学杂志》2013年第3期249-253,共5页Chinese Journal of Microecology

基　　金：昆明理工大学2012年创新基金(2012BA141)

摘　　要：目的从纳帕海湿地土样中分离和培养低温菌及其噬菌体,并对其特性进行研究。方法分离纯化低温宿主菌,采用"双层平板法"分离获得噬菌体,通过16S rRNA基因分析对宿主菌进行初步鉴定,对噬菌体进行电镜形态观察,并进行噬菌体基因组酶切片段长度多态性分析及噬菌体生理特性研究。结果从纳帕海土样中分离获得一株裂解性低温噬菌体,命名为SV-12,其宿主菌S-12鉴定为恶臭假单胞菌(Pseudomonas putida)。噬菌体SV-12有囊膜,头部为典型的正六边形,立体对称结构,直径约68.7 nm;尾管长约122.5 nm,直径约25 nm;在4℃时具有侵染活性,4～25℃均能产生边缘清晰、透明的噬菌斑。最适感染温度约为10℃,pH耐受范围较广,在pH=10时具有最多出斑数。结论 SV-12属于肌尾噬菌体科,为裂解性噬菌体,对氯仿极度敏感。基因组为dsDNA,大小约为74 kb。Objective To isolate and characterize a cold-active bacterium-specific phage isolated from the soil samples of Napa Lake wetland. Methods Bacterial strains isolated from Napa Lake wetland were used as the host cells to isolate and purify bacteriophages by double-layer plate method. Host cell was identified by 16S rRNA gene analysis. The morphology of the isolated phage was observed by electron microscope. Restriction fragment length polymorphism （RFLP） analysis of genomic DNA, and physiological analysis were further carried out to characterize the phage. Results A lytic cold-active bacteriophage, designated as SV-12, was isolated from the soil samples of Napa Lake wetland. Based on the 16S rRNA sequence analysis, the host strain S-12 was identified as a member of Pseudomonas put# da, The bacteriophage SV-12 had an isometric head （ about 68.7 nm in diameter） , a long tail （ about 122.5 nm in length and 25 nm in width） , and envelope was detected. Physiological analysis results showed that SV-12 had infection activity at 4 ℃ and clear and trans- parent plaques were formed on double-layer plates at 4 to 25 ℃. Its optimum infection temperature and pH were about 10 ℃ and 6, re- spectively. Conclusion SV-12 belongs to Myoviridae family and is a lytic phage. It is very sensitive to chloroform. The genome of SV-12 consists of double-stranded DNA and is approximately 74 kb in size.

关 键 词：纳帕海湿地 低温噬菌体 生理特性 恶臭假单胞菌 

分 类 号：R378.991[医药卫生—病原生物学]