Progress in the identification of nonmotile Bacteroidaceae from dental plaque

Over the last decade, biochemical and chemical analyses have been used widely to study the intrageneric structure of Bacteroidaceae. New chromogenic substrates (e.g., naphthylamide-linked compounds) and fluorogenic substrates (e.g., 4-methylumbelliferyl or 7-amido-4-methyl-coumarin compounds) can be used to identify certain species within a few hours under aerobic conditions. Clarification of the taxonomy of many oral anaerobic species that are now considered important putative periodontal pathogens has permitted the development of panels of both polyclonal and monoclonal antibodies for their detection. Similarly, both DNA and RNA gene probes, derived through nucleic acid sequence analysis, have been constructed for several species; many such probes are now commercially available. In the long term, the application of these techniques will lead to a better understanding of the distribution, transmission, and ecological and clinical importance of many species that have hitherto remained poorly characterized.