Streptococcus tigurinus is a novel species of viridans streptococci, shown to cause severe invasive infections such as infective endocarditis, spondylodiscitis and meningitis. S. tigurinus belongs to the Streptococcus mitis group and is most closely related to Streptococcus mitis, Streptococcus oralis, Streptococcus pneumoniae, Streptococcus pseudopneumoniae and Streptococcus infantis. The pres...

Streptococcus pseudopneumoniae is a recently described member of the Streptococcus mitis/oralis group of viridans streptococci that shares some characteristics with Streptococcus pneumoniae (1). Key characteristics of S. pseudopneumoniae are the absence of pneumococcal capsule, insolubility in bile, resistance or indeterminate susceptibility to optochin when incubated in 5% CO2 but susceptibili...

We aimed to obtain insights on the nature of a collection of isolates presumptively identified as atypical Streptococcus pneumoniae recovered from invasive and non-invasive infections in Spain. One-hundred and thirty-two isolates were characterized by: optochin susceptibility in ambient and CO(2)-enriched atmosphere; bile solubility; PCR-based assays targeting pneumococcal genes lytA, ply, pspA...

BACKGROUND Benign vocal fold lesions, including cysts, nodules, polyps, and Reinke's edema, are common causes of hoarseness and subsequent voice disorders. Given the prevalence of these lesions, disease etiology and pathophysiology remain unclear and their microbiota has not been studied to date secondary to the paucity of available biopsies for investigation. We sought to characterize and comp...

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 phenotypi...

Streptococcus pneumoniae (pneumococcus) is a major human pathogen. The main pneumococcal autolysin LytA and the pneumolysin Ply are two of the bacterium's most important virulence factors. The lytA- and ply-related genes are also found in other streptococci of the Mitis group (SMG). The precise characteristics of the lytA-related-but not the ply-related-genes of SMG and their prophages have bee...

The identification of commensal streptococci species is an everlasting problem due to their ability to genetically transform. A new challenge in this respect is the recent description of Streptococcus pseudopneumoniae as a new species, which was distinguished from closely related pathogenic S. pneumoniae and commensal S. mitis by a variety of physiological and molecular biological tests. Forty-...