Phylum Firmicutes, Class Clostridia, Order Clostridiales, Family Clostridiaceae, Genus Clostridium, Cluster I (Clostridium sensu
stricto), Clostridium acetobutylicum McCoy, Fred, Peterson and Hastings 1926, emend. Keis, Shaheen and Jones 2001.
Historical synonyms: Clostridium acetonobutylicum Prevot 1938, Clostridium acetobutyricum Prevot 1940.
Gram-positive (Gram-negative in older cultures) straight rods, 0.5-0.9 x 1.6-6.4 µm,
motile by peritrichous flagella. Granulose (a starch-like polymer) is often present.
Spores are oval, subterminal, slightly swelling the cell.
Colonies on blood agar are nonhemolytic,1-5 mm in diameter, flat to raised, granular,
grayish-white, glossy surface, translucent to semiopaque with irregular margins and
occasionally with a mosaic internal structure. Grows weakly in nutrient broth. Grows in
broth media (nutrient broth) with a fermentable carbohydrate added. Abundant gas is
produced in glucose agar deep cultures. Cultures in PYG broth (peptone, yeast extract
& glucose) are turbid with a smooth sediment and have pH 4.5-5.0 after 5 days of
incubation. A fermentable carbohydrate, biotin, and p-aminobenzoic acid are required
for growth. No growth in 6.5% NaCl medium. Optimum growth temperature 37 ºC.
Source: soil, lake sediment, well water, clum gut, bovine feces, canine feces, human feces.
Susceptible to clindamycin, chloramphenicol, erythromycin, penicillin G, rifampicin and tetracycline.
Culture supernatants are not toxic to mice. Toxin is not produced. Non-pathogenic for laboratory animals.
- 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.
- Keis S., Shaheen R. and Jones D.T., 2001. Emended descriptions of Clostridium acetobutylicum and Clostridium beijerinckii,
and descriptions of Clostridium saccharoperbutylacetonicum sp. nov. and Clostridium saccharobutylicum sp. nov. IJSEM 51,
Products in PYG broth are butyric, acetic, and lactic acids; acetone, CO2 and large amounts of hydrogen. H2 is produced very
abundantly. Milk reaction: negative. Meat is not digested.
Positive results for acetyl methyl carbinol production, DN-ase, esculin hydrolysis, gelatin liquefaction, starch hydrolysis, neutral red
reduction, N2 atmospheric fixation, substrate utilized and/or acid produced from: arabinose, dextrin, fructose, galactose, glucose,
lactose, maltose, mannose, pectin, salicin, starch, sucrose & xylose (weak).
Negative results for catalase, nitrate reduction, indole production, lecithinase, lipase, urease, substrate utilized and/or acid produced
from: D- or L-arabitol, glycerol & ribose.
Variable results for hydrolysis of casein, H2S production, substrate utilized and/or acid produced from: amygdalin, cellobiose, dulcitol,
esculin, glycogen, inositol, inulin, mannitol, melezitose, melibiose, raffinose, rhamnose, sorbitol, sorbose, trehalose & turanose
(c) Costin Stoica