牙龈卟啉菌全染色体探针的鉴定

THE IDENTIFICATION OF WHOLE GENOMIC DNA PROBE FOR PORPHYROMONAS GINGIVALIS

①目的 对地高辛标记的牙龈卟啉菌 47A 1全染色体探针的敏感性和特异性进行检测。②方法采用斑点印迹法和狭缝印迹法 ,将获得的牙龈卟啉菌 47A 1全染色体探针与口腔中 14种共 18株常见细菌DNA进行杂交鉴定 ,检测其敏感性和特异性。③结果 探针敏感性达到 1ng同源序列水平 ,与 18株口腔内常见菌种的杂交结果显示 ,除与 3株同种菌杂交外 ,与中间型普氏菌、产黑色素普氏菌、栖牙类杆菌、多形类杆菌以及不解糖卟啉菌等相关菌存在不同程度的交叉反应 ,采用氯化锂法纯化探针对杂交结果没有明显影响。④结论 牙龈卟啉菌47A 1全染色体探针敏感性较高但特异性不强 ,其制备容易 ,化学性质稳定 。

Objective\ To detect the sensitivity and specificity of whole genomic DNA probe of Porphyromonas gingivalis. Methods\ The purified DNA of Porphyromonas gingivalis 47A 1 was digoxigenin labelled by a random primer technique using the DIG DNA Labelling Kit as the whole genomic DNA probe. Using dot blot and slot blot methods to test the sensitivity and specificity of the probe with 18 strains of oral bacteria.\ Results\ The whole genomic DNA probe of Porphyromonas gingivalis could detect homologous target DNA fixed to nylon membrane at 1ng sensitivity. It could detect effectively all three strains of Porphyromonas gingivalis, including 47A 1, ATCC33277 and W83. Also it cross reacted with several black pigmented Bacteroides species, including Prevotella intermedius ATCC 25261, Prevotella melaninogenicus ATCC13040, Prevotela denticola ATCC33185, Porphyromonas asaccharolyticus NCTC9337 and Bacteroides thetaiotamicron CDC1041 A.\ Conclusion\ The sensitivity of Porphyromonas gingivalis whole genomic DNA probe is high but its specificity is not so notable.