Lactobacillus

A genus of gram-positive, microaerophilic, rod-shaped bacteria occurring widely in nature. Its species are also part of the many normal flora of the mouth, intestinal tract, and vagina of many mammals, including humans. Lactobacillus species are homofermentative and ferment a broad spectrum of carbohydrates often host-adapted but do not ferment PENTOSES. Most members were previously assigned to the Lactobacillus delbrueckii group. Pathogenicity from this genus is rare.