Taxonomy
Morphology
Cultural characteristics
Biochemical characters
Ecology
Pathogenicity
References
Phylum Bacillota (Firmicutes), Class Clostridia, Order Eubacteriales, Family Clostridiaceae, Genus Clostridium, Cluster I
(Clostridium sensu stricto), Clostridium scatologenes (Weinberg and Ginsbourg 1927) Prévot 1948.
Historical synonym: Clostridium scatol Fellers and Clough 1925, Bacillus scatologenes Weinberg and Ginsbourg 1927.
Gram-positive straight rods, 0.5-1.6 x 3.1-21.2 µm. Motile by peritrichous flagella.
Spores are oval, terminal/subterminal, slightly swell the cell. The cell wall is
susceptible to dissolution by lysozyme.
Surface colonies on blood agar are alpha-hemolytic, 0.5-2.0 mm in diameter, circular,
convex, translucent, gray, with an entire or scalloped margin, a matt surface, and a
granular or mottled internal structure. Cultures in PYG broth are turbid with a smooth
sediment and have a pH of 5.2–5.4 after incubation for 5 days. Optimum temperature
for growth is 30-37 ºC; can grow at 25 but not at 45 ºC. Growth is inhibited by 6.5%
NaCl, pH 8.5 or 20% bile. Abundant gas is produced in PYG deep agar cultures. No
aero-tolerance. Products in PYG broth include large amounts of acetic and butyric
acids; abundant hydrogen is produced.
Isolated from soil, contaminated food, feces of infants undersized at birth.
Culture supernatants are not toxic for mice. Toxin is not produced. Nonpathogenic 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,
Springer, 738-828.
- Smith L.D.S. and Hobbs G., 1974. 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.
Milk reaction is negative. Meat is not digested.
Positive results for ammonia production, H2S production, neutral red reduction, substrate utilization and/or acid production from:
fructose, glucose, glycerol & mannose.
Negative results for casein hydrolysis, gelatin hydrolysis, lecithinase, lipase, nitrate reduction, starch hydrolysis, urease,
Voges-Proskauer reaction, substrate utilization and/or acid production from: adonitol, amygdalin, cellulose, dulcitol, erythritol,
galactose, glycogen, inositol, inulin, lactose, maltose, mannitol, melezitose, melibiose, raffinose, sorbitol, sorbose, starch, sucrose &
trehalose.
Variable results for esculin hydrolysis, hippurate hydrolysis, indole production, resazurin reduction, substrate utilization and/or acid
production from: arabinose, cellobiose (weak), rhamnose, ribose, salicin (weak) & xylose.
(c) Costin Stoica