A closer look at the insertion within helix 54 of the 23S-rRNA of the genus Corynebacterium (and related taxa).

Direct sequencing of the insertion in helix 54 of the 23S-rRNA of different strains of 8 species of the genus Corynebacterium was performed in order to determine the extent of variations of these strains. The results demonstrated that there is considerable variation within different strains of a single species. While this clearly jeopardizes the usefulness of the insertion with regard to species-specific diagnostic probes, the variations were found to concentrate within two clearly defined regions comprising the ascending and descending parts of the distal helix of a putative stemlike secondary structure. The remainder of the insertion sequences seem to be fairly constant within a single species while displaying considerable differences toward sequences of other species of the same genus.