斑点热群立克次体HL-93株ompA蛋白基因片段的克隆及序列分析

Cloning and sequence analysis of genomic fragment encoding 190KD protein antigen of HL-93 spotted fever group Rickettsiae

以根据立氏立克次体分子量为１９０×１０＾３蛋白抗原基因序列设计的一对引物Ｒｒ１９０．７０ｐ和Ｒｒ１９０．６０２ｎ，用聚合酶链反应技术从斑点热群立克次体ＨＬ－９３株染色体ＤＮＡ中扩增出了１９０×１０＾３蛋白基因的部分片段。通过载体质粒ｐＧＥＭ－Ｔ将该部分基因片段克隆进入了大肠杆菌ＪＭ１０１，并进行了核苷酸序列分析。

Genomic fragment encoding 190kD protein antigen was amplified from spotted fever group . ( SFG ) rickettsiae HL-93 strain by polymerase chain reaction with a pair of primers Rr 190. 70p and Rr 190. 602n which were designed from DNA sequences encoding 190kD protein antigen of R.rickettsii and cloned into E . coli JM 101 by using plasmid vector PGEM-T . The genomic fragment was sequenced and compared with that of R. rickettsii and R . Japonica which were reported previously. The results showed that 31 and 24 nucleotides in HL-93 strain differed from that in R. rickettsii and R. japonica , respectively. The genetic homology was 94% and 95. 5% respectively ,and amino acid homology was 87% and 89% respectively. All data suggest that HL-93 strain is a new member of SFG rickettsiae.