Identification of P. gingivalis P. intermedia P. nigrescens by microarray

Objectives: The aim of this study was to identify three kinds of black-pigmented periodontal pathogens P. gingivalis(Pg), P. intermedia (Pi) and P. nigrescens (Pn) by 16S rRNA gene and microarray. Methods: We designed a pair of universal primers which can amplify a section of conservative domain of bacterial 16S rDNA based sequences of 16S rDNA in Genebank. Then we designed the specific oligonucleotide probes for Pg, Pi and Pn based on the sequences of the conservative domain. Standard bacterial genomic DNAs were amplified using the designed universal primers by PCR , and labeled by cy5 at the same time, the products of PCR hybridized with the microarray in which the specific probes were added. The results of hybridization were screened by confocal laser scanner. Results: The results of hybridization showed that the specific probes of Pg, Pi and Pn on microarray reacted only with corresponding PCR products of Pg, Pi and Pn , and did not react with others. Conclusions: The method of 16S rDNA and microarray could be useful to identify Pg, Pi and Pn, and had high specifity. It will be developed into a kind of clinical bacterial detective system. This research was supported by National Natural Science Foundation of China No.30271413