BACKGROUND The roles of group C and F streptococci in causing endemic pharyngitis are still controversial, although group C streptococci are implicated in the outbreaks of pharyngitis and associated disorders. AIM The aim of this study was to determine the prevalence and the role of these groups of β-hemolytic streptococci in acute pharyngitis with emphasis on the Streptococcus anginosus grou...

Streptococcus species are the most abundant genera in the oral microbiota. The prevalence of antibiotic resistant oral streptococci is on the increase and the most reported antibiotic resistance profile in oral streptococci include, among several antibiotics, resistance to βlactams antibiotics, macrolides and tetracycline. Several studies have shown that majority of the antibiotic resistance ge...

We investigated the initial adhesion in vitro of oral streptococci to porcelain inlays. Four strains of streptococci, Streptococcus mitis NCTC12261, Streptococcus oralis ATCC9811, Streptococcus sanguis ATCC10556 and Streptococcus sobrinus OMZ176, were used in this study. The disc specimens were made of porcelain, composite resin cement and human enamel. These specimens, with or without a saliva...

Wide-zone, alpha-hemolytic streptococci are potential sources of false-positive throat cultures since they can be misinterpreted as beta-hemolytic streptococci. However, quantitative information regarding their occurrence in sick children was not available. Throat swabs from 312 children with pharyngitis were processed conventionally and also with pour-plate methods and examination of the posit...

A virulence factor denotes a bacterial product or strategy that contributes to virulence or pathogenicity. Streptococci produce a variety of protein toxins and enzymes that are capable of killing host cells and breaking down cell constituents, presumably to provide nutrients for the bacteria or to promote their spread. Some of these secreted products are hemolysins, streptokinases, hyaluronidas...

Hybridoma technology was used to produce a set of monoclonal antibodies against a purified polypeptide fragment of type 24 streptococcal M protein to delineate the protective determinants of M protein exposed on the surface of the virulent streptococci. Several hybridoma antibodies were found to be opsonic against the homologous type streptococci. At least two of these antibodies (IIC3.7 and II...

1. No connection can be demonstrated between grouping of non-hemolytic streptococci based upon fermentation reactions, and grouping based upon immunological reactions. 2. A classification of non-hemolytic streptococci can be effected by studying the complement fixation reactions between the streptococci and their antisera. 3. The arrangement of the streptococci in such a classification depends ...

Intact bacterial membranes have been isolated from protoplasts prepared from Group A streptococci by a cell wall-dissolving enzyme. A membrane fraction with identical chemical and serological properties has been obtained by differential centrifugation of mechanically disrupted streptococci. The membrane is chemically distinct from the cell wall and is composed of 72 per cent protein, 26 per cen...

A rapid CAMP test for the presumptive identification of Streptococcus agalactiae (Lancefield group B) is described. Sheep erythrocytes, sensitized by staphylococcal beta-lysin and suspended in phosphate-buffered saline, were used to determine the lytic capacity of the neutralized supernatant fluids of 4-h broth cultures of streptococci being tested. A total of 96.2% of 130 group B streptococci ...

Six tests commonly used for the presumptive identification of group D streptococci were evaluated. Strains tested included 282 group D streptococci and 366 non-group D. Ratios of percentages of group D to non-group D strains which gave positive reactions for each test are as follows: bile-esculin, 100:2; salt tolerance, 88:24; heat tolerance, 100:80; SF broth, 86:1; KF broth, 99:40; and methyle...