Phylum Firmicutes, Class Clostridia, Order Clostridiales, Family Clostridiaceae, Genus Clostridium, Cluster I (Clostridium sensu
stricto), Clostridium tertium (Henry 1917) Bergey, Harrison, Breed, Hammer and Huntoon 1923.
Historical synonyms: Bacillus tertius Henry 1917, Henrillus tertius (Henry 1917) Heller
1922, Plectridium tertium (Henry 1917) Prevot 1938.
Gram-positive straight rods, 0.5-1.4 x 1.5-10.2 µm, occuring singly or in pairs. Motile
by peritrichous flagella. Spores are oval, terminal/subterminal, swelling the cell;
spores are formed readily in most media incubated anaerobically, but not under
Colonies on the surface of blood agar incubated anaerobically are 2-4 mm in diameter,
circular, low convex, have slightly irregular margins, are white to gray, and have a matt
surface and usually a mottled or granular internal structure. Hemolysis is variable and,
when present, colonies may be alpha- or beta-hemolytic.
Surface colonies after aerobic incubation are 1 mm, circular with entire edges, dome
shaped, and have an opalescent appearance. Colonies in agar are small and
Aerotolerance, grow on the surface of freshly prepared blood agar incubated in air. Cultures in PYG broth are turbid with a smooth,
ropy or flocculent sediment. Moderate growth in nutrient broth. Growth is inhibited by 6.5% NaCl, or 20% bile. Growth is stimulated by
Optimum temperature for growth is 37 ºC, range 25-50 ºC.
Products in PYG broth: acetic, lactic and butyric acids and hydrogen. Abundant gas is produced in PYG deep agar cultures.
Isolated from soil, guano in Antarctica; the nares of a beagle dog; feces of healthy neonates and infants; appendices of healthy adults;
the feces or colonic mucosa of healthy adults; osteomyelitis in a dog; infection in a calf; a variety of conditions in humans including
brain abscess, the gingival sulcus of two patients with periodontitis, infections related to the intestinal tract, soft tissue infections, war
wounds, and blood.
Susceptible to chloramphenicol and tetracycline.
Non-pathogenic for laboratory animals. Toxin is not produced.
Bile acid deconjugation and delta(4)-steroid dehydrogenase activity that may be related to the etiology of colon cancer have been
Weakly pathogenic or relatively non-pathogenic when compared with several other species of Clostridium in a study of experimental
intestinal strangulation in monoassociated gnotobiotic rats. Pneumatosis cystoides intestinalis can occur in these monoassociated
Increases the severity of a lethal enteritis induced by Clostridium difficile in gnotobiotic newborn hares.
- 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., 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.
No meat digestion or curd production.
Positive results for hydrogen, chitinase, DN-ase, esculin hydrolysis, neuraminidase, neutral red reduction, resazurin reduction,
substrate utilization and/or acid production from: cellobiose, fructose, galactose, glucose, glycogen, lactose, maltose, mannitol,
mannose, melibiose, ribose, salicin, starch & sucrose.
Negative results for casein hydrolysis, gelatin hydrolysis, H2S production, indole production, lecithinase, lipase, urease,
Voges-Proskauer reaction, substrate utilization and/or acid production from: adonitol, cellulose, erythritol, glycerol & inositol.
Variable results for ammonia production, starch hydrolysis, nitrate reduction, substrate utilization and/or acid production from:
amygdalin, arabinose, dulcitol, esculin, inulin (weak), melezitose, raffinose, rhamnose (weak), sorbitol, sorbose, trehalose & xylose.
(c) Costin Stoica