Clostridium perfringens curd formed and disrupted
by intense gas production (left)
Cultural characteristics
Biochemical characters
Phylum Firmicutes, Class Clostridia, Order Clostridiales, Family Clostridiaceae, Genus Clostridium, Cluster I (Clostridium sensu
Clostridium perfringens (Veillon and Zuber 1898) Hauduroy, Ehringer, Urbain, Guillot and Magrou 1937.
Clostridium perfringens has been divided into five types (A, B, C, D, and E) on the basis of production of major lethal toxins. Type A
produces alpha toxin; type B produces alpha, beta, and epsilon toxins; type C produces alpha and beta toxins; type D alpha and
epsilon toxins; type E produces alpha and iota toxins.
Historical synonyms: B
acillus perfringens Veillon and Zuber 1898,
Bacterium welchii Migula 1900.
Gram-positive straight rods, 0.6-2.4 x 1.3-19.0 µm, occuring singly or in pairs in PYG
(peptone yeast extract containing glucose) broth cultures. Nonmotile. Spores are oval,
large, central/subterminal, swelling the cell; spores are rarely seen in vivo or in the
usual in vitro conditions. Approximately three-quarters of strains possess a capsule
that is composed largely of polysaccharides.
Surface colonies on blood agar plates are 2-5 mm in diameter, dome-shaped,
translucent with a glossy surface, gray to grayish yellow.  Colonies in agar are usually
lenticular. The type of hemolysis present depends on both the species of blood and
the type of
Clostridium perfringens being examined; the three types of hemolysins that
may be produced in varying quantities are designated alpha, delta, and theta.
On rabbit, sheep, cow, horse, or human blood, most strains produce a narrow zone of complete hemolysis due to the theta toxin and
a surrounding zone of incomplete hemolysis due to the alpha toxin. Some type B and C strains may produce a very wide zone of
haemolysis on sheep or cow blood due to delta toxin.
Moderate growth in nutrient broth; rapid growth in broth with fermentable carbohydrate. Cultures in PYG broth are turbid with a smooth
sediment and have a pH of 4.8–5.6 after 1 week incubation. Abundant gas is produced in PYG deep agar cultures.
Growth is inhibited by 6.5% NaCl but not by 20% bile. Grows at: 20-50 ºC, optimum at 37-45 ºC. Optimum growth at pH 5.5-8.0.
Isolated from soil, marine sediments, wounds, feces, clothing, raw milk, cheese, semipreserved meat products, intestinal contents of
animals. This species is more widely spread in nature than any other pathogenic microorganism. Humans and animals frequently

Clostridium perfringens as part of the normal endogenous flora.
Most strains are susceptible to bacteriocins produced by enterococci.
Some soil isolates of
Clostridium perfringens produce inhibitors that are active against some or all of Clostridium botulinum types A,
B, E, and F.
Clostridium perfringens also produces bacteriocins that are active against
other strains of
Clostridium perfringens. Bacteriocin production and resistance to that
bacteriocin is related to the presence of a plasmid.
Most beta-lactams, particularly penicillin G, are quite active against
C. perfringens.
Aminoglycosides are inactive against
C. perfringens. Plasmid-mediated resistance
C. perfringens to clindamycin-erythromycin, to tetracycline-chloramphenicol, and to
tetracycline alone has been described.
Pathogenic for man and animals. Pathogenic for laboratory animals; type strain's
culture supernatants are  toxic to mice.
Produces soluble substances that cause a variety of toxic effects in in vitro and  in vivo
conditions. Can produce up to 16 toxins in various combinations, including 4 major
toxins (alpha, beta, epsilon and iota) and other lethal toxins (perfringolysin O,
enterotoxin and beta2 toxin). Alpha toxin is essential in the production of gas gangrene
of humans and several animal species. Beta toxin is responsible for necrotizing
enteritis and enterotoxemia in neonatal individuals of sheep, goat, cattle. Epsilon toxin
is responsible for enterotoxemia  in sheep and goats. Enterotoxin is responsible for
gastrointestinal disease in humans and dogs, horses, pigs, goat. Iota toxin produce enteritis at sheep and cattle and enterotoxemia
in rabbits. Perfringolysin O has possible synergism with alpha and epsilon toxins. Beta2 toxin produce neonatal diarrhea in pigs.
Clostridium perfringens is the species of Clostridium most commonly isolated from infections in humans; such infections are often
polymicrobial. It is most commonly recovered from infections derived from the colonic flora (e.g., peritonitis, intra-abdominal abscess,
and soft tissue infections below the waist).
  1. 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.
  2. 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.
  3. Uzal F.A., Vidal J.E., McClane B.A. and Gurjar A.A., 2010. Clostridium perfringens toxins involved in mammalian veterinary
    diseases. The Open Toxinology Journal, 3, 24-42.
  4. Secasiu V., 2001. Boli produse de germeni din genul Clostridium. In: Boli infectioase ale animalelor, Moga Manzat R., Ed. Brumar,
    Timisoara, 481-612.
Products in PYG broth are butyric, acetic, and lactic acids. H2 is produced very
abundantly. Milk reaction: positive (stormy). Meat digestion is variable.

Positive results for hydrolysis of gelatin, H
2 production, lecithinase, neutral red
reduction,  substrate utilized and/or acid produced from: fructose, galactose (weak),
glucose, lactose, maltose, mannose & sucrose.

Negative results for indole production, lipase, substrate utilized and/or acid
produced from: arabinose, mannitol, melezitose,  rhamnose, salicin & xylose.

Variable results for DN-ase, H
2S production, nitrate reduction, casein hydrolysis,
esculin hydrolysis, hippurate hydrolysis, starch hydrolysis, resazurin reduction,
urease, Voges-Proskauer reaction, substrate utilized and/or acid produced from:
amygdalin (weak), cellobiose, dulcitol, glycogen, glycerol (weak), inositol, inulin
(weak), melibiose (weak), raffinose, ribose, sorbitol, sorbose (weak), starch &
Clostridium perfringens
(c) Costin Stoica
Culture media
Biochemical tests
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