Abstract:

Objective To clone and detect the lactate dehydrogenase (LDH) gene of Veillonella dispar(V.dispar)　and its adjacent gene and  provide a theoretical basis for prevention and treatment of dental caries. Methods LDH gene and its adjacent gene were detected by PCR method and were inserted into a cloning vector  PMD18-T to transform E.coil JM109.The sequencing  was performed after PCR identification and restriction enzyme digestion.Results The PCR product was specific,and the size of the product was   2 300 bp.The sequencing data were analyzed by BLAST software and  the result indicated that they contained three pieces of genes which were DNA gyrase A,LDH,and an unknown product.The homology of the sequencing result was 99 % compared with the LDH gene of Streptococcus(S.mutans) which was reported in GenBank.And the sequence had been submitted to the NCBI GenBank,and the accession number was EU518464.Conclusion The LDH gene of Veillonella dispar was successfully cloned, and it is proved to have a full reading framework,through the analysis of the  gene sequences  and amino acids.

Key words: Veillonella dispar;lactate dehydrogenase;gene cloning;　sequence determination