Infection of S. anginosus could occur frequently in oral squamous cell carcinoma and that dental plaque could be a dominant reservoir of the S. anginosus.
We studied the pheno-and genotypes of an oral Granulicatella elegans strain in comparison with those of a blood-derived isolate which caused infective endocarditis. The two isolates exhibited identical biochemical characteristics and had the same drug MICs. Their genotypes were indistinguishable, indicating that these were from the same clone. The transmission of G. elegans from the oral cavity thus should be noted as a possible cause of infective endocarditis.
A novel antigen that induces nitric oxide (NO) synthesis by murine peritoneal exudate cells (PEC) was prepared from a culture supernate of Streptococcus anginosus NCTC 10713 in dialysed medium by column chromatography with DEAE-Sephacel followed by size-exclusion high performance liquid chromatography (HPLC). A chemical analysis of the S. anginosus antigen (SAA) revealed that it mainly consisted of carbohydrates (rhamnose, N-acetylglucosamine, glucose and galactose), smaller quantities of protein and a trace amount of phosphorus. The SAA stimulated PEC from C57BL/6N mice to produce NO and accumulate induced NO synthetase (iNOS) mRNA in a dose-dependent manner, reaching a plateau with 10±30 ìg=ml. Furthermore, a reverse transcription-PCR assay revealed that SAA 10 ìg=ml could induce mRNA accumulation of tumour necrosis factor-á, interleukin (IL)-1â and IL-6 as well as iNOS. In contrast, RantzRandall antigen (RRA), a carbohydrate antigen prepared from the organisms, could not induce NO synthesis or cause the accumulation of iNOS mRNA, although cytokine production was observed after stimulation. The SAA-induced NO synthesis, but not the cytokine production, was sensitive to heat. Furthermore, an immunoblot analysis of SAA indicated that the 43-kDa protein band reacted with anti-SAA but not anti-RRA antibodies. In immunodiffusion, SAA reacted with both anti-SAA and anti-RRA antibodies, and the precipitin bands formed crossing lines, suggesting that SAA could possess two different antigenic components ± one that reacts speci®cially with anti-SAA antibodies and another that has an identity similar to that of RRA. Taken together, SAA, a novel antigen of S. anginosus, was found to induce NO synthesis as well as produce in¯ammatory cytokines in murine PEC. It is suggested that the protein molecule of SAA may exclusively induce NO synthesis, and its carbohydrate component(s) could have a relationship to cytokine production.
Abiotrophia adiacens and Abiotrophia defectiva, previously referred to as nutritionally variant streptococci, Streptococcus adjacens and Streptococcus defectivus, respectively, are causes of infective endocarditis. We describe a method of identifying these two species and also of distinguishing them from 15 other major etiological pathogens of infective endocarditis by means of 16S rRNA gene PCR amplification followed by restriction fragment length polymorphism analysis (PCR-RFLP). The 16S rRNA genes were successfully amplified with a set of universal primers from all 17 species of bacteria examined, including viridans group streptococci. The RFLP patterns of A. adiacens and A. defectiva obtained by HaeIII or MspI digestion were readily distinguished from each other and from those of other bacteria. When PCR analysis was performed with the supernatant of a suspension of a boiled colony, the 16S rRNA genes of 80 of 82 isolates (97%) of A. adiacens and all isolates (11 of 11) of A. defectiva were amplified. The HaeIII RFLP patterns of the isolates were the same as those of the corresponding type strains, although 28% of A. adiacens isolates revealed intraspecies polymorphism. The detection limit of this method was 0.1 pg of genomic DNA, as assessed by using the digoxigenin-labeling DNA detection system. Thus, the PCR-RFLP analysis that we developed is applicable for the routine detection of Abiotrophia from clinical specimens.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.