Page:Bergey's manual of determinative bacteriology.djvu/599



Bu.ty.ri.bac.te'ri.um. Gr. noun butyrum butter; M.L. adj. butyricus butyric; Gr. dim. noun bacterium a little rod; M.L. neut.n. Butyribacterium the butyric bacterium.

Straight or slightlj' curved rods. Non-motile. Gram-positive. Anaerobic to microaerophilic. Ferment carbohydrates and lactic acid, forming acetic and butyric acids and carbon dioxide. Generally catalase-negative but sometimes weakly positive. From the intestinalcontents of vertebrates so far as known.

The type species is Butyribacterium rettgeri Barker and Haas.

1. Butyribacterium rettgeri Barker and Haas, 1944. (Strain 32, Lewis and Rettger. Jour. Bact., 40, 1940, 298; Barker and Haas, Jour. Bact., 47, 1944, 303.)

ret'tge.ri. M.L. gen. noun rettgeri of Rettger; named for L. F. Rettger, one of the bacteriologists who first isolated this organism.

Rods straight or slightly curved, 0.7 by 2.3 microns, occurring singly, in pairs and in short chains. Non-motile. Not encapsulated. No branched cells observed, but some cells have swollen club-shaped ends. Gram-positive.

Glucose-cysteine agar colonies: Circular, translucent, often with opaque center, grayish white with yellowish tinge, convex when small, later umbonate, glistening, smooth, finely granular, edges entire or finely irregular; develop slowly, attaining a diameter of 1.5 mm in 7 days.

Tryptone-yeast extract-lactate agar colonies: Similar to those described above except larger (2 mm in 4 days at 37° C.); pulvinate rather than umbonate in cross sections.

Glucose-cysteine broth: Abundant turbidity and sediment; no pellicle.

Agar stab (King and Rettger's medium, Jour. Bact., 44, 1942, 302): Heavy growth in 2 days. Gas production often causes slight splitting of agar.

Acetic and butyric acids and carbon dioxide produced from glucose and maltose; occasionally a small amount of visible gas is produced. Lactic acid fermented readily without visible gas. Arabinose, xylose, lactose, sucrose, trehalose, rhamnose, mannitol, sorbitol, dulcitol and glycerol are not fermented.

Not proteolytic.

Indole not produced.

Hydrogen sulfide not produced.

Generally catalase-negative.

Anaerobic.

Temperature relations: Optimum, 37° C. Minimum, 15° C. Maximum, between 40° and 45° C.

Source: Isolated from the intestinal contents of a white rat.

Habitat: Presumably found generally in the intestines of mammals.

Genus III. Zymobaeterium Wachsman and Barker, 1954

(Jour. Bact., 68, 1954, 400.)

Zy.mo.bac.te'ri.um. Gr. noun zyme leaven, ferment; Gr. dim. neut.n. bacterium a small rod; M.L. neut.n. Zymobaeterium ferment rodlet.

Rods which occur singly or in chains. Non-motile. Gram-positive. Anaerobic or microaerophilic. Catalase-negative. Carbohydrates are utilized, glucose being converted mainly to ethanol and carbon dioxide with small amounts of acetic and possibly lactic and formic acids.

The type species is Zymobaeterium oroticum Wachsman and Barker.