Gram-positive rods or coccobacilli, nonspore-forming; fermentative metabolism, obligately saccharoclastic, at least half of end product carbon is lactate; facultatively anaerobic; gelatin not liquefied, indole and H2S not produced, catalase and oxidase negative; complex nutritional requirements for amino acids, peptides, nucleic acid derivatives, vitamins, salts, fatty acids, and carbohydrates; growth temperature range 2-53 °C; optimal pH 5.5-6.2. Found in dairy products, foods, beer, wine, fruits, water, soil, and sewage; they are a part of the normal flora in the mouth, intestinal tract, and vagina of humans and many animals. Nonpathogenic or pathogenicity is restricted to persons with an underlying disease.
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