我国Q热立克次体分离株cbhE'和cbbE'基因的扩增

Amplification of the cbhE' and cbbE' plasmid gene of Caxiella burnetii isolates from china

用聚合酶链反应（ＰＣＲ）首次对我国Ｑ热立克次体分离株质粒上的特异ＤＮＡ片段ｃｂｈＥ＇和ｃｂｂＥ＇基因进行扩增，目的序列分别为２５８ｂｐ和１４８５ｂｐ。实验结果显示，在我国分离的８株Ｑ热立克次体株中，３株出现了２５８ｂｐ阳性扩增带，５株有１４８５ｂｐ扩增带；两对引物只扩增Ｑ热立克次体的ＤＮＡ。研究证明，我国分离的Ｑ热立克次体株也分别带有ＱｐＨＩ和ＱｐＲＳ型质粒，存在急、慢性分离株之分，但分离株所含质粒类型并不完全与其菌株感染的临床表现相吻合。

The partial soquence of the cbhE' and total sequence of the cbbE' plasmid gene in Cox iellaburnetii isolates in China were firstly amplified by polymerase chain reaction .PCR ). The expected amplification sequences were 258bp and 1 485bp fragments ,raspectively. The results showed that three in eight chinese isolates from various sources had 258bp amplification band , while another five isolates appeared as 1485bp fragments on agarose gel electrophoresis. it suggested that Cox iella burnetii isolates from China also carry the plasmid QpHI or QpRS. Specificity tests demonstrated that the two primer pairs only amplified DNA from Cox iella burnetii isolates and no amplihtcation products were obtained in other microorganisms. Although the correlation between the human disease state and plasmid specificity has been described , our studies indicated that the gene specificity was not completely identical to pathotype.