BACKGROUND Cases of infective endocarditis (IE) require prompt etiological diagnosis for effective treatment. Molecular methods can aid in rapid and reliable diagnosis of culture-negative IE cases. We evaluated the utility of 16S rDNA PCR and sequencing in determining the causative agents of IE in valve tissues, especially when specimens were obtained after initiation of antimicrobial therapy. ...

rhizoctonia zeae causes root rot and sheath blight on corn (zea mays) and several other gramineous plants. in order to determine the genetic diversity of the r. zeae population in mazandaran and golestan provinces, samples were collected from cultivatd soils of both provinces in 2011 and 2012.the identity of isolates as r. zeae were verified by amplification and sequencing of the 18s and 28s rd...

"Tropheryma whippelii"-associated infections are usually confirmed histopathologically by using light microscopy. PCR assays targeting the 16S rRNA gene (16S rDNA) of "T. whippelii" are increasingly being applied for this purpose. Compared to microscopic analysis, PCR seems to be more sensitive, as indicated by the fact that several cases of Whipple's disease with negative histopathological fin...

16S rDNA PCR and sequencing are powerful tools for bacterial detection and identification, although their routine use is not currently widespread in the field of clinical microbiology. The availability of pyrosequencing now makes 16S rDNA assays more accessible to routine diagnostic laboratories, but this approach has had limited evaluation in general diagnostic practice. In this study we evalu...

Intragenomic variation is the molecular within genome among repetitive DNA. As a multigene family, nuclear ribosomal DNA (rDNA) has been widely used in fungal taxonomy for their ease amplification and suitable variability to attain various levels of taxonomic resolution. At intraspecific level, rDNA believed be under concerted evolution internal transcribed spacers (ITS) region actually accepte...

Bacteria associated with the parthenogenetic troglobiont sand fly Deanemyia maruaga were characterized by sequencing cloned 16S rDNA PCR products. Eleven novel partial 16S rDNA sequences, with varying degrees of similarity to Actinobacteria, were identified. None of the sequences identified had homology to those known from parthenogenesis-inducing bacteria.

Experience with a MicroSeq D2 large-subunit (LSU) ribosomal DNA (rDNA) sequencing kit for identification of yeast species commonly encountered in the mycology laboratory at Mayo Clinic is described here. A total of 131 isolates of yeasts recovered from clinical specimens were included in the study. Phenotypic methods used for initial identification included germ tube formation, urease productio...

Identification of clinically significant nocardiae to the species level is important in patient diagnosis and treatment. A study was performed to evaluate Nocardia species identification obtained by partial 16S ribosomal DNA (rDNA) sequencing by the MicroSeq 500 system with an expanded database. The expanded portion of the database was developed from partial 5' 16S rDNA sequences derived from 2...

The phylogenetic relationships of Enterobacter sakazakii strains were investigated using 16S ribosomal DNA (rDNA) and hsp60 sequencing. Each analysis distributed E. sakazakii strains among four clusters, indicating substantial taxonomic heterogeneity. The E. sakazakii type strain 16S rDNA sequence was 97.8% similar to that of Citrobacter koseri but 97.0% similar to that of Enterobacter cloacae.

Background: The aim of the study was to analyze the performance of PCR-DGGE based assay and its applicability as a tool for the identification of bacteria in the middle ear of children with otitis media with effusion (OME). Methods: The middle ear effusions from 20 children with OME were analyzed both by bacterial culture and by 16S rDNA-gene-targeted PCR assay, DGGE fingerprinting and sequenci...