Atypical Structure of the 23S Ribosomal RNA Molecule in Certain Oral Bacteria

Abstract

Ribosomal RNA (rRNA) isolated from Wolinella recta and seven related bacteria was examined by agarose gel electrophoresis. The 23S rRNA molecule could not be detected in W. recta, Wolinella curva, Bacteroides gracilis, or Bacteroides ureolyticus. In place of the 23S molecule, there were three smaller molecules of approximately 1700, 650, and 600 bases designated 23S alpha, 23S beta, and 23S delta, respectively. An intact 23S rRNA molecule could be isolated from Wolinella succinogenes, Campylobacter concisus, and Campylobacter sputorum. The cleavage sites of the W. recta 23S rRNA molecule were located by direct RNA sequence analysis and were found to be in similar locations, nucleotides 546 and 1180, as cleavage sites described in other prokaryotes. The presence or absence of the 23S rRNA molecule may be a useful marker for these micro-organisms.

An intervening sequence (IVS) in the 16S rRNA gene of the eubacteriumHelicobacter canis

“…Whilst the S. typhimurium and Y enterocolitica 23S rRNA gene IVs are small and noncoding, the larger IVSs found in Leptospira vary from 485 to 759 nts and contain a small ORF (121-133 amino acids) oriented so that the sense strand appears in the transcript rRNA (24). It was earlier observed that the 23S rRNA appears as three smaller molecular species in Wolinella recta (Campylobacter rectus), W.curva (C. curvus), Bacteroides gracilis and B. ureolyticus (25), four species belonging to RNA Superfamily VI (4), which also contains the genus Helicobacter.…”

Rapid identification of Actinobacillus actinomycetemcomitans based on analysis of 23S ribosomal RNA

“…Photograph of rRNA specimens isolated from single colonies of clinical isolates of A. actinomycetemeomitans (lanes 1 and 4), H. apinofyliilus (lanes 2, 3) and H. .segnis (lanes 5, 6) grown on blood agar (lanes 1,2,5) and chocolate agar (lanes 3, 4, 6). dopseudomonas sphaeroides (16), Agrobacteriutn tutnefacietis (6), Bdellovibrio bacteriovorus (19), Bacteroides graeilis and Bctcteroides ureolytieus (30) and the oral bacteria Campylobacter rectus and Catnpylobacter curva (30). However, no other bacteria growing on TSBV selective medium and resembling A. actitiomyeetemeotnitatis in colony morphology or catalase reactivity exhibited the same rRNA pattern as A. actinomycetetncotnitans.…”