Phylum Firmicutes, Class Clostridia, Order Clostridiales, Family Clostridiaceae, Genus Clostridium, Cluster I (Clostridium sensu
stricto), Clostridium acidurici corrig. (Liebert 1909) Barker 1938.
Historical synonyms: Bacillus acidi-urici Liebert 1909.
Gram-variable to Gram-negative rods, 0.5-0.7 x 2.5-4.0 µm; occur singly. Motile by
peritrichous flagella. Spores are oval, terminal/subterminal, swelling the cell.
Sporulation occurs most reliably on chopped-meat uric-acid agar slants incubated at
30 ºC for 1 week in an N2 atmosphere.
Surface colonies on uric acid agar are spreading,1-2 mm, rhizoid, transparent or
opaque, white or colorless, and raised or flat, clearing the agar. No growth in gelatin or
milk, or on egg-yolk or blood agar, or the usual laboratory media.
Broth cultures supplemented with 0.3% uric acid have a smooth sediment with no
turbidity and a pH of 7.4-7.7 after incubation under N2 for 6 days. Most rapid growth
occurs in media at an initial pH of 7.6–8.1; there is poor growth below pH 6.5 or above
9.0. Grows at 19-37 ºC. Uric acid, xanthine, guanine, or hypoxanthine is required as a
carbon and energy source. Products in PY-urate broth are acetate, NH3, and CO2. No carbohydrates are fermented.
The type strain are resistant to erythromycin, penicillin and tetracycline; it is moderately sensitive to clindamycin and chloramphenicol.
Source: soil, chicken droppings, wild birds.
Culture supernatants of the type strain are not toxic to mice.
- N.A. Logan and P. De Vos, 2009. Genus I. Clostridium Prazmowski 1880. In: (Eds.) P.D. Vos, G. Garrity, D. Jones, N.R. Krieg, W.
Ludwig, F.A. Rainey, K.-H. Schleifer, W.B. Whitman. Bergey’s Manual of Systematic Bacteriology, Volume 3: The Firmicutes,
- Smith L.D.S. and Hobbs G., 1975. Genus III. Clostridium Prazmowski 1880. In: (Eds.) Buchanan R.E. and Gibbons N.E., Bergey’s
Manual of Determinative Bacteriology, Eighth Edition , The Williams & Wilkins Company, Baltimore, 551-572.
Negative results for H2 production, indole production, esculin hydrolysis, starch hydrolysis, nitrate reduction, substrate utilization
and/or acid production from: amygdalin, cellobiose, fructose, glycogen, lactose, maltose, ribose, starch, sucrose, trehalose & xylose.
(c) Costin Stoica