Several characteristics of the 16S rRNA gene, such as its essential function, ubiquity, and evolutionary properties, have allowed it to become the most commonly used molecular marker in microbial ecology. However, one fact that has been overlooked is that multiple copies of this gene are often present in a given bacterium. These intragenomic copies can differ in sequence, leading to identificat...

BACKGROUND 16S rRNA methylase-producing Gram-negative bacteria are highly resistant to all clinically important aminoglycosides. We analyzed clinical strains of 16S rRNA methylase-producing Acinetobactor baumannii and Pseudomonas aeruginosa obtained from clinical isolates in medical settings in Vietnam. METHODS From 2008 to 2011, 101 clinical strains of A. baumannii and 15 of P. aeruginosa we...

Ever since Carl Woese introduced the use of 16S rRNA genes for determining the phylogenetic relationships of prokaryotes, this method has been regarded as the "gold standard" in both microbial phylogeny and ecology studies. However, intragenomic heterogeneity within 16S rRNA genes has been reported in many investigations and is believed to bias the estimation of prokaryotic diversity. In the cu...

Here we present the first description of the presence of two distinct types of 16S rRNA genes in the genome of a (eu)bacterium, Thermobispora bispora. We cloned and determined the nucleotide sequences of all four rRNA operons of T. bispora. Sequence comparisons revealed that the genome of T. bispora contains two distinct types of 16S rRNA genes, each type consisting of two identical or nearly i...

Two nested PCRs for the detection of Mycobacterium ulcerans were compared by using a collection of 65 clinical specimens. The first method amplifies the gene coding for 16S rRNA, and the second method amplifies a repetitive DNA sequence. The sensitivities of bacterioscopy, culture, 16S rRNA gene PCR, and repetitive-sequence PCR were 29, 34, 80, and 85%, respectively. Compared to the 16S rRNA ge...

The bulge-helix-bulge (BHB) motif recognised by the archaeal splicing endonuclease is also found in the long processing stems of archaeal rRNA precursors in which it is cleaved to generate pre-16S and pre-23S rRNAs. We show that in two species, Archaeoglobus fulgidus and Sulfolobus solfataricus, representatives from the two major archaeal kingdoms Euryarchaeota and Crenarchaeota, respectively, ...

Direct examination † Culture Molecular identification Ring of epithelial cells Giant cells Caseous necrosis Altered leukocytes Reference M. tuberculosis ± + IS6110 + + + – (6) M. avium 183 NR NR NR + NR + + NR NR (7) M. avium subsp. hominissuis 34 NR NR NR + IS1245 NR NR NR NR (5) M. haemophilum 39 NR NR + + 16S–23S rDNA + + + – (8) M. lentiflavum 3 SE Cured + + 16S rRNA + + NR + (9) M. bohemic...

Introduction Many studies have shown epidemiological links between strains isolated in tap water, and those isolated from patients. Molecular methods linked to PCR are more reliable and faster for identification of             non- tuberculous mycobacteria(NTM). In this study molecular methods were used for identification and typing of NTM. Materials and Methods Five hundred ml of 85 water ...

The potential of a solution-based hybridization assay using peptide nucleic acid (PNA) molecular beacon (MB) probes to quantify 16S rRNA of specific populations in RNA extracts of environmental samples was evaluated by designing PNA MB probes for the genera Dechloromonas and Dechlorosoma. In a kinetic study with 16S rRNA from pure cultures, the hybridization of PNA MB to target 16S rRNA exhibit...