Analysis of stable low-molecular-weight RNA profiles of members of the family Rhizobiaceae.

Staircase electrophoresis in polyacrylamide gels was used to analyze the stable low-molecular-weight (LMW) RNA profiles of 24 type strains belonging to the family Rhizobiaceae. This new electrophoretic technique results in good separation of the molecules forming the LMW RNA profiles. Differences in the number and distribution of the RNA bands in these profiles allowed us to identify differences among the 24 strains assayed. Species assignments based on LMW RNAs proved to be consistent with the established taxonomic classification. Analysis of the data obtained and the corresponding dendrograms revealed relationships between genera and species; these relationships were essentially the same as those obtained with other techniques, such as DNA hybridization and 16S rRNA sequencing. Use of the technique described here, with which it is possible to analyze a large number of strains in a short time, permits rapid identification of species belonging to the family Rhizobiaceae and should in the future facilitate biodiversity studies and detection of new species.