血链球菌特异DNA片段探针制备及临床应用

目的 探讨血透链球菌特异ＤＮＡ片段探针制备及临床应用。方法 采用特异引物的ＰＣＲ扩增及运用探针进行Ｓｏｕｔｈｅｒｎ杂交，斑点杂交来检测链球菌同源序列，结果：Ｓ３４ｓｒ，Ｓ３４非１和ＡＴＣＣ１０５５６的ＤＮＡ含有同源序列，另有两株血链球菌临床分离株五点杂交结果为弱阳性，其它３０余株细胞杂交结果阳性，结论 血链球菌ＡＴＣ－Ｃ１０５５６菌株中的ｎｉｆ基因为血链球菌的特异基因，该基因在血链球菌蛋白的表达及

Preparation of Streptococcus sanguis DIG-labeled DNA Probes and Clinical Application

Objective:To investigate oral Streptococci nif gene. Methods: According to the 800 base pairs(bp) sequence, a couple of special prime was designed, which were 5'TAGTTGAAGCGATTAAAGCG 3' and 5' TCGTCGTGAAAGCCAAA 3'. DIG labeled DNA probes of ATCC10556 800bp DNA fragment and 559bp DNA fragment were made. By using Southern blotting and dot blotting, more than 30 bacterial strains were checked. Results: 559bp sequence was according with the reported results, and the Southern blot results showed that S34sr, S34 no 1 strains had homologicous sequence with ATCC10556, two strains of Streptococcus sanguis were weak positive, and other strains were negative.Conclusion: Streptococcus sanguis ATCC10556 strain contained exactly nif gene and nif gene may be the special gene of Streptococcus sanguis ATCC 10556.