title: recA-based PCR assay for accurate differentiation of Streptococcus pneumoniae from other viridans streptococci.
abstract: Proper identification of Streptococcus pneumoniae by conventional methods remains problematic. The discriminatory power of the 16S rRNA gene, which can be considered the "gold standard" for molecular identification, is too low to differentiate S. pneumoniae from closely related species such as Streptococcus pseudopneumoniae, Streptococcus mitis, and Streptococcus oralis in the routine clinical laboratory. A 313-bp part of recA was selected on the basis of variability within the S. mitis group, showing <95.8% interspecies homology. In addition, 6 signature nucleotides specific for S. pneumoniae were identified within the 313-bp recA fragment. We show that recA analysis is a useful tool for proper identification to species level within the S. mitis group, in particular, for pneumococci.
authors.affiliation: University of Zurich, Institute of Medical Microbiology, Gloriastrasse 30/32, CH-8006 Zurich, Switzerland. azbinden@imm.uzh.ch
authors.forename: A
authors.initials: A
authors.lastname: Zbinden
authors.forename: N
authors.initials: N
authors.lastname: Köhler
authors.forename: G V
authors.initials: GV
authors.lastname: Bloemberg
mesh_terms: D001431:Bacteriological Techniques / Q000379:methods*; D017931:DNA Primers / Q000235:genetics; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D006801:Humans; D008969:Molecular Sequence Data; D011008:Pneumococcal Infections / Q000175:diagnosis*; D016133:Polymerase Chain Reaction / Q000379:methods*; D011110:Polymorphism, Genetic; D011938:Rec A Recombinases / Q000235:genetics*; D017422:Sequence Analysis, DNA; D017385:Sequence Homology; D034363:Viridans Streptococci / Q000145:classification* / Q000235:genetics* / Q000302:isolation & purification
chemical_list: D017931:DNA Primers; D004269:DNA, Bacterial; D011938:Rec A Recombinases