Cellulose digesting bacteria from human feces.

Anaerobic, gram-negative, nonsporing rod-shaped bacteria that digest wet-ballmilled filter paper have been isolated in numbers of over 10(8) per gram wet weight of feces, about 0.3% of total viable bacteria, from feces of two humans. Significant numbers of cellulolytic bacteria were not detected in four other humans. One of the strains is a Bacteroides sp., which only slowly digests cellulose and produces succinate, acetate, and H2 in carbohydrate fermentation.