伴放线放线杆菌全染色体DNA探针的制备和鉴定

The preparation and identification of whole genomic DNA probe of Actinobacillus actinomycetcmcomitans

本研究的目的是制备伴放线放线杆菌全染色DNA探针,并评价其特异性和敏感性。抽提标准菌株Aa Y4 DNA,经^(32)P标记后制成探针,然后用斑点杂交法鉴定探针性质。结果Aa全染色体DNA探针的灵敏性为8×10~2纯菌或1ng同源DNA,探针与口腔常见菌的杂交显示仅与嗜沫嗜血杆菌有较弱的交叉反应。提示^(32)P标记Aa全染色体DNA探针的敏感性、特异性均较高,且方便实用,有临床推广应用价值。

This study was to prepare a whole-chromosomal DNA probe of Aa, and to evaluate the specificity and sensitivity of the probe. The whole chromosomal DNA, extracted from representive strains of Aa Y4, was labelled with 32 P by random priming. Then the characteristics of the probe was determined by dot blot assay. The whole genomic probe specific for Aa succeeded in detecting 8×102 cells/Ing purified target DNA of the homologous species. Among the detected oral bacteria, only Haemophilus aphrophilus showed a weak cross - reactivity, which can be easily distinguished by naked eye. In addition, the probe identified all Aa strains. The Aa DNA probe promises a considerable prospect for clinical application.