Bioinformatical analysis of avirulent strain-specific DNA fragments from Streptococcus mutans of serotype c / 实用口腔医学杂志

ABSTRACT

Objective:To explore avirulent strain-specific new genes or new functions of already known genes from Streptococcus mutans of serotype c.Methods:Twenty-six DNA fragments unique to avirulent strain of Streptococcus mutans were sequenced.The sequences of these presumptive avirulence DNA fragments were subjected to homology search through BLASTn and BLASTx in public database,and their putative biological functions were analyzed.Results:The size of the DNA fragments ranged from 113 bp to 776 bp.The average G+C content was 38.27%,similar to that of the gene-codingsequences in Streptococcus mutans strain UA159 whose genome sequences were just completed.Seven clones were picked repeatedly.Of the nineteen DNA fragments,eight potentially represented new DNA fragments were registered in GenBank.The remaining DNA fragments showed high homology to known genes of Streptococcus mutans strain UA159.Conclusions: The gene analysis and identification supply the groundwork for further study of gene functions of the avirulent strain of Streptococcus mutans serotype c.