The development of a 16S rRNA gene based PCR for the identification of Streptococcus pneumoniae and comparison with four other species specific PCR assays

Abstract

Abstract

Background: Streptococcus pneumoniae is one of the most frequently encountered pathogens in humans but its differentiation from closely related but less pathogenic streptococci remains a challenge.

Methods: This report describes a newly-developed PCR assay (Spne-PCR), amplifying a 217 bp product of the 16S rRNA gene of S. pneumoniae , and its performance compared to other genotypic and phenotypic tests.

Results: The new PCR assay designed in this study, proved to be specific at 57°C for S. pneumoniae , not amplifying S. pseudopneumoniae or any other streptococcal strain or any strains from other upper airway pathogenic species. PCR assays (psaA, LytA, ply, spn9802-PCR) were previously described for the specific amplification of S. pneumoniae , but psaA -PCR was the only one found not to cross-react with S. pseudopneumoniae .

Conclusion: Spne-PCR, developed for this study, and psaA-PCR were the only two assays which did not mis-identify S. pseudopneumoniae as S. pneumoniae . Four other PCR assays and the AccuProbe assay were unable to distinguish between these species.