Identification of Selenomonas species by whole‐genomic DNA probes, sodium dodecyl sulfate‐polyacrylamide gel electrophoresis, biochemical tests and cellular fatty acid analysis

摘要

Nonisotopic, whole‐genomic DNA probes, sodium dodecyl sulfate‐polyacrylamide gel electrophoresis (SDS‐PAGE), biochemical tests in microtiter trays and cellular fatty acid (CFA) analysis were compared for the identification of 5 oral Selenomonas species. DNA probes were prepared by biotin‐labeling DNA extracted from the type strains ofSelenomonas noxia, Selenomonas flueggei, Selenomonas artemidis, Selenomonas infelix and Selenomonas spittigena.The probes were hybridized with DNA from 21 reference strains, 18 fresh isolates ofSelenomonasspecies, and 21 strains of other oral gram‐negative species. Target DNAs were obtained by in situ extraction of colonies blotted onto filter paper. Streptavidin‐linked alkaline phosphatase was used to detect homologous reactions of probe and target DNA. EachSelenomonasspecies DNA probe reacted with reference strains of only that species. AllSelenomonasstrains that reacted with the DNA probe for a particular species gave similar biochemical test results, SDS‐PAGE protein profiles, and CFA profiles to those of the type strain of the corresponding species. All the methods tested were useful for identifying the species, and all yielded similar identifications of the fresh isolates. The DNA probes, however, had the potential for identifying Selenomonas species directly from primary isolation plates or p