Phylum Firmicutes, Class Clostridia, Order Clostridiales, Family Clostridiaceae, Genus Clostridium, Cluster I (Clostridium sensu
stricto), Clostridium carnis (Klein 1904) Spray 1939.
Historical synonyms: Bacillus carnis Klein 1904, Plectridium carnis Prevot 1938.
Gram-positive straight to slightly curved rods, 0.5-1.1 x 1.6-9.9 µm, occuring singly or
in pairs. Motile by peritrichous flagella. Spores are oval, terminal/subterminal,
swelling the cell; sporulation occurs most readily in chopped-meat broth cultures
incubated for 24 hours.
Surface colonies on anaerobic blood agar plates are pinpoint–2 mm, convex to slightly
peaked, translucent, smooth, grayish white, with a mottled or mosaic internal structure.
They may be slightly beta-hemolytic. Aerotolerant. Colonies will grow on blood agar
plates incubated aerobically, but spores are not formed under aerobic conditions.
Cultures in PYG broth are turbid with a smooth sediment and have a pH of 4.9–5.4 after
incubation for 1 week. Slight growth in nutrient broth. Growth is inhibited by 6.5% NaCl,
20% bile, or a pH of 8.5. Grow optimally at 37 ºC. Variable, weak growth at 25 or 45 ºC.
Growth is stimulated by fermentable carbohydrates. Products in PYG broth are acetic,
lactic and butyric acids and hydrogen. Abundant gas is produced in PYG deep agar cultures.
Isolated from soil, putrefying meat, soft tissue infections and blood in humans, human feces, clinical specimens in animals.
Susceptible to chloramphenicol, erythromycin, penicillin and tetracycline.
Pathogenic for laboratory animals. Toxin is produced.
- 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.
H2 is produced very abundantly. Milk reaction and meat digestion are negative.
Positive results for DNase, esculin hydrolysis, neutral red reduction, resazurin reduction, substrate utilized and/or acid produced from:
amygdalin (weak), cellobiose, glucose, maltose, mannose, salicin (weak) & sucrose.
Negative results for H2S production, indole production, lecithinase, lipase, nitrate reduction, starch hydrolysis, Voges-Proskauer,
substrate utilized and/or acid produced from: adonitol, arabinose, cellulose, dulcitol, erythritol, esculin, glycogen, glycerol, inositol,
inulin, mannitol, melezitose, melibiose, raffinose, rhamnose, ribose, sorbitol, sorbose, trehalose & xylose.
Variable results for substrate utilized and/or acid produced from: fructose, galactose, lactose & starch (weak).
(c) Costin Stoica