Clostridium difficile infection is an increasing problem in hospitals worldwide, mainly due to the recent emergence of a hypervirulent C. difficile strain. C. difficile PCR ribotyping, based on size variation of the 16S-23S rRNA intergenic spacer region (16S-23S ISR), is widely used in Europe for molecular epidemiological investigation. The mechanism underlying the 16S-23S ISR size variations i...

Low-cost and rescue treatments for Helicobacter pylori infections involve combinations of several drugs including tetracycline. Resistance to tetracycline has recently emerged in H. pylori. The 16S rRNA gene sequences of two tetracycline-resistant clinical isolates (MIC = 64 microg/ml) were determined and compared to the consensus H. pylori 16S rRNA sequence. One isolate had four nucleotide sub...

We characterized the intracellular symbiotic bacteria of the mulberry psyllid Anomoneura mori by performing a molecular phylogenetic analysis combined with in situ hybridization. In its abdomen, the psyllid has a large, yellow, bilobed mycetome (or bacteriome) which consists of many round uninucleated mycetocytes (or bacteriocytes) enclosing syncytial tissue. The mycetocytes and syncytium harbo...

Two recently published but independently derived structures, namely the X-ray crystallographic structure of ribosomal protein S7 and the "binding pocket" for this protein in a three-dimensional model of the 16S rRNA, have been correlated with one another. The known rRNA-protein interactions for S7 include a minimum binding site, a number of footprint sites, and two RNA-protein crosslink sites o...

Phylogenetic relationships among species of the genus Ureaplasma were elucidated by analyzing 16S rRNA sequence information. The 16S rRNA genes of six strains of the mammalian Ureaplasma species were amplified by PCR and were sequenced directly by a primer walking method. The phylogenetic tree based on the nucleotide sequence of the 16S rRNA genes corresponded to the evolutionary history of the...

To facilitate the differential identification of the genus Streptomyces, the 16S rRNA genes of 17 actinomycetes were sequenced and screened for the existence of streptomycete-specific signatures. The 16S rDNA of the Streptomyces strains and Amycolatopsis orientalis subsp. lurida exhibited 95-100% similarity, while that of the 16S rDNA of Actinoplanes utahensis showed only 88% similarity to the ...

In vivo [methyl 3H]-labeled SV40 19S and 16S mRNA species were purified and their internal methylation as well as their capping structures analyzed. SV40 viral mRNA sedimenting in the 19S region contains approximately equal proportions of m7GpppAm and m7Gppm6Am, while the 16S mRNA contains mainly m7Gpppm6Am. N6 methyl adenosine is located internally within the RNA chains of both the 19S and 16S...

How good is electrospray ionization MS (ESI-MS) at detecting weakly bound complexes? Richard Griffey and colleagues at Ibis Therapeutics report a spectrum of a complex held together by a single hydrogen bond. They also describe the binding stoichiometry for complexes of multiple ligands with RNA and an example where a ligand binds to two different sites. The key is choosing the right conditions...

16S ribosomal RNA currently represents the most important target of study in bacterial ecology. Its use for the description of bacterial diversity is, however, limited by the presence of variable copy numbers in bacterial genomes and sequence variation within closely related taxa or within a genome. Here we use the information from sequenced bacterial genomes to explore the variability of 16S r...