非同位素标记脆弱类杆菌DNA探针的研究

为探索应用分子生物学技术检测厌氧菌的方法，选择脆弱类村抽提其染色体ＤＮＡ，用生物素和地高辛配基标记制备ＤＮＡ探针，检测厌氧和需氧菌９４株，临床标本４５份，并和＾３２Ｐ标记探针及培养生化鉴定比较，该探针可检出临床上常见的类杆菌属细菌与其它细菌无交叉反应，结果：地高辛配基标记探针的灵敏度（１０ｐｇＤＮＡ和１０＾３ＣＦＵ／ｍｌ）接近＾３２Ｐ标记探针的灵敏度（１ｐｇＤＮＡ和１０＾３ＣＦＵ／ｍｌ）。地高辛配

A study of non radioactive DNA probe for detection of Bacteroides fragilis

This study was designed to explore a rapid, specific sensitive and simple molecular biological method which was applied for the detection of anagrobes. In this study we chose the commom anaerobes in clinic Bacteroides fragilis(B.f)to extract the total DNA and prepare the DNA probes labeled with non radioactive biotin and digoxigenin. 94 clinical isolates from anaarobes and aerobes as well as 45 clinical specimens were tested with these probes, compared with 32p labeled probes, anaerobic culture and biochemical reactions. The results showed that the common Bacteroides in clinic might be detected with these probes. No cross reactions with other anaerobes and aerobes were found. The sensitivity of digoxigeninated probes was 10 pg of DNA and 10 3 CFU/ml of Bacteroides, Comparable to 32p labeld probes (1 pg of DNA and 10 3 CFU/ml)and higher than biotinated probes (100pg DNA and 10 4 CFU/ml). When compared with culture and biochemical identification of bacteroides, the sensitivity of digoxigeninated and biotinated probes were 89.47% and 53.63%, the specificity were 92.31% and 84.61% respectively. These data revealed that the chromosomal DNA probes of Bacteroides fragilis could detect the common clinical Bacteroides with high sensitivity and specificity.