Catalase-producing strains of streptococci.

The genus Streptococcus includes organisms which are homofermentative, facultative with respect to oxygen, fastidious in their nutrient requirements, without cytochrome system, and are therefore considered to be catalase negative. Recent work in this laboratory revealed two strains of several hundred streptococci, screened from silage fermentations, that were capable of producing catalase. They appeared to be closely related to Streptococcus faecalis var. liquefaciens. The work reported here describes the cultural, morphological, and physiological characteristics of the catalase-producing isolates.