Culture and Physiology of a Starch-digesting Bacterium (bacteroides Amylophilus N. Sp.) from the Bovine Rumen1

Studies in this and other laboratories have disclosed a variety of starch-digesting rumen organisms, including Streptococcu bouis (Hungate et al., 1952), several cellulolytic strains (Hungate, 1950), and various non-cellulolytic bacteria (Gall et al., 1947; Gall and Huhtanen, 1951; Huhtanen and Gall, 1953a, b; Bryant and Burkey, 1953a,b; Jayko, 1953; McPherson, 1953; van der Wath, 1948) as well as protozoa of the genera Entodinium and Diplodinium (Ferber, 1928) and Isotriha (Gutierrez, 1955, Sugden and Oxford, 1952). Starch digestion by most of the bacteria has been discovered after they have been isolated on other substrates. It seemed of interest to investigate whether use of starch in initial agar dilution series would disclose starch-digesting bacteria not previously encountered. Starch digesters tentatively identified as S. bovi8 and as the weakly cellulolytic, butyric acid-producing rods (Hungate, 1950) were encountered and, in addition, rod shaped bacteria different from any previously described amylolytic organisms, and considered to be a new species, Bacteroides amylophilus.