In Vitro Amplification, Molecular Cloning And Preparation Of Nucleic Acid Probe Of The Specific Gene Fragment Of Porphyromonas Gingivalis And Their Application

Since bacteria, anaerobic bacteria in particular, have been associated with oral diseases, many scholars have suggested that some bacteria be made index in routine oral examination and diagnosis. Nevertheless, It is difficult to identify definitely bacteria by conventional detection methods. The present study aims to, with Porphyromonas gingivalis(Pg) as its subject, discover new methods of bacteriological identification by molecular biological techniques and thus provide some basis for basic research and clinical application.1 By PCR-Technique Acquirement and Identification of Specific Pg Gene Fragment 1.1 Successful Acquirement of Specific Pg Gene FragmentA pair of primers were designed according to the sequence of the gene encoding the fimbrial subunit protein(fimA) of Pg(Dickinson 1988), which amplified the fragment at 504-1045 bp of 5' termini of this gene. The total length of the fragment was 542bp. With the international standard strain Pg381 DNA as the amplified template, recombinant plasmid pUC13Bgl2.1 containing PgfimA gene as positive control template, recombinant plasmid pAA2097 containing Aa gene as negative control template, after 35 cycles of amplification (Each cycle included denaturing at 94X2 for 30 s, annealing at 55℃ for 1 min and extending at 72℃ for 1 min), the products were separated by agarose gel electrophoresis before...