Phylogenetic Diversity among Unknown Oral Bacterial Species

Recently many new bacterial genera and species, such as genus Slackia, Eggerthella, Cryptobacterium and Mogibacterium, have been proposed on the basis of phylogenetic analysis and DNA-DNA similarity data. These organisms, isolated from periodontal pockets and other oral infectious lesions, are asaccharolytic anaerobic gram positive rods (AAGPR), and have been proven to be difficult to culture and unreactive in conventional biochemical tests. Molecular systematic techniques, including 16S rRNA gene sequencing analysis, have demonstrated that there is more diversity than previously thought in these AAGPR species. In addition, these sequences dates can be helpful for the construction of specific PCR primers for use in the rapid detection and identification of previously undescribed taxa. A complete description of the microbial flora associated with oral infections could lead to potential benefits in the elucidation of disease causation, and the development of novel diagnostic tools.