The diagnosis of invasive pneumococcal disease (IPD) is currently based on culture methods, which lack sensitivity, especially after antibiotic therapy. Molecular methods have improved sensitivity and do not require viable bacteria; however, their use is complicated by reports of low specificity with some assays. The present study investigated the specificity of a real-time PCR targeting lytA f...

The vast majority of streptococci colonizing the human upper respiratory tract are commensals, only sporadically implicated in disease. Of these, the most pathogenic is Mitis group member, Streptococcus pneumoniae Phenotypic and genetic similarities between streptococci can cause difficulties in species identification. Using ribosomal S2-gene sequences extracted from whole-genome sequences publ...

Although often considered a strict human pathogen, Streptococcus pneumoniae has been reported to infect and cause pneumonia in horses, although the pathology appears restricted compared to that of human infections. Here we report on the molecular characterization of a group of S. pneumoniae isolates obtained from horses in England and Ireland. Despite being obtained from geographically distinct...

The usefulness and reliability of partial sequence analysis of the manganese-dependent superoxide dismutase gene (sodA), autolysin (lytA) gene amplification and species-specific PCR based on the D-alanine:D-alanine ligase (ddl) gene for differentiating each member of the mitis group of the genus Streptococcus was investigated. On the phylogenetic tree based on sodA partial sequences (366 bp) fr...

It is difficult to separate Streptococcus pneumoniae from the genotypically similar species Streptococcus mitis and Streptococcus oralis, which are commensals of the human oral cavity. A novel nucleic acid amplification technique, loop-mediated isothermal amplification (LAMP), which amplifies DNA under isothermal conditions (63 degrees C) with high specificity, efficiency, and rapidity, was exa...

Streptococcus pneumoniae is an important human pathogen that has an absolute nutritional requirement for choline. Replacement of this amino alcohol in a synthetic medium by structural analogues, such as ethanolamine (EA cells), leads to alterations in several physiological properties including cell separation (Tomasz, 1968, Proc Natl Acad Sci USA 59: 86–93). Identical changes including chain fo...