Streptococcus

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Streptococcus, genus of spherical, gram-positive, aerobic bacteria. The streptococci occur in pairs or chains, and some species are pathogenic in humans. Streptococcal infections include strep throat, scarlet fever, erysipelas, puerperal fever, and some pneumonias. The drugs of choice for treating such infections are penicillin and erythromycin. Cultures of nonpathogenic lactic streptococci are used in the fermentation of dairy products such as cheese and buttermilk.

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