Taxonomy
Morphology
Cultural characteristics
Biochemical characters
Ecology
Pathogenicity
References
Phylum Actinomycetota, Class Actinomycetes, Order Actynomycetales, Suborder Actinomycinae, Family Actinomycetaceae, Genus
Actinomyces, Actinomyces bovis Harz 1877.
Historical synonyms: Discomyces bovis (Harz) Rivoltat 1878, Nocardia bovis (Harz) Blanchard 1896, Streptothrix bovis (Harz) Chester
1901, Proactinomyces bovis (Harz) Henrici 1939.
Gram-positive irregular, diphtheroid or branched rods, occurring filaments. Non-motile.
Non-spore-forming.
Colonies are small, circular, flat, granular to smooth, soft, and occasional may be
filamentous, like those of A. israelii, after 24 h on BHI agar and blood agar; after 7-14
days the colonies are 0.5-1.0 mm in diameter, convex, circular, opaque, white, with
smooth or granular surface. Some strains may produce irregular, heaped up colonies,
like those of Actinomyces israelii.
In BHI broth growth diffuse with settles to the bottom and a flaky appearance when is
shaken. Some isolates produce a more viscous growth and others a granular growth,
like A. israelii, but granules are softly and easily broken. Some strains are serophilic.
facultative anaerobe, grows best in CO2 presence. Grows optimally at 37 ºC.
Alpha-haemolysis is not present. Beta haemolysis may occur.
The normal habitat is the oral cavity of animals (cattle, swine, horses, and other).
Sensitive to penicillin, streptomycin, tetracyclines, cephalosporin and lincomycin.
Causes actinomycosis in cattle, swine, horses and other animals.
Experimental infections in hamsters and mice.
- Slack J.M., 1975. Genus Actinomyces Harz 1877. In: Buchanan R.E. and Gibbons N.E. (Editors), Bergey’s Manual of Determinative
Bacteriology, Eight Edition, The Williams & Wilkins Company, Baltimore, 660-667.
- Johnson J.L., Moore L.V.H., Kaneko B. and Moore W.E.C., 1990. Actinomyces georgiae sp. nov. , Actinomyces gerencseriae sp.
nov. , Designation of Two Genospecies of Actinomyces naeslundii, and Inclusion of A. naeslundii serotypes II and III and
Actinomyces viscosus serotype II in A. naeslundii Genospecies 2. Int J Syst Bacteriol Vol. 40, No. 3, 273-286.
- Funke G., von Graevenitz A., Clarridge III J.E., and Bernard K.A., 1997. Clinical Microbiology of Coryneform Bacteria. Clinical
Microbiology Rewiews Vol. 10, No. 1, p. 125-159.
Positive results for esculin hydrolysis, H2S production, reduction of methyl red, starch hydrolysis, acid production from: fructose,
galactose, glucose, inositol, lactose, maltose, starch and sucrose.
Negative results for catalase, gelatin hydrolysis, indole production, urease, Voges-Proskauer test, acid production from: amygdalin,
arabinose, cellobiose, esculin, inulin, mannitol, melezitose, melibiose, raffinose, ribose and trehalose.
Variable results for nitrate reduction, acid production from: glycerol, mannose, rhamnose, salicin and xylose.
(c) Costin Stoica