Phylum Actinobacteria, Class Actinobacteria, Subclass Actibacteridae, Order Actynomycetales, Suborder Actinomycinae, Family
Actinomycetaceae, Genus Actinomyces, Actinomyces europeus Funke, Alvarez, Pascual, Falsen, Akervall, Sabbe, Schouls, Weiss and
Historical synonyms : EF group 43 bacteria (Arcanobacterium bernardiae-like bacteria,
CDC coryneform group E-like bacteria).
Gram-positive short, irregular rods, sometimes arranged in clusters; no filament
formation. Non-motile. Non-spore-forming.
Colonies are smooth, translucent grayish, 0.5 mm in diameter on Columbia agar
(Difco) supplemented with 5% horse blood at 37 ºC in air plus 5% CO2.
Facultative anaerobic. CAMP reaction is negative. Some strains exhibits very slight
beta-hemolysis on sheep blood agar.
Isolated from human abscesses. Habitat is not known.
The pathogen role is unclear.
- Funke G., Alvarez N., Pascual C., Falsen E., Akervall E., Sabbe L., Schouls L., Weiss N., and Collins M.D., 1997. Actinomyces
europeus sp. nov., isolated from human clinical specimens. Int. J. Syst. Bacteriol. Vol. 47, No. 3, 687-692.
Description is based mostly on API CORYNE , API ZYM, API 50CH (with API 50 CHE medium) results.
Positive results for esterase C4 , ester lipase C8, alpha- and beta-galactosidase, alpha-glucosidase, leucine arylamidase, valine
arylamidase, acid production from: D-glucose, maltose, galactose & fructose.
Negative results for alkaline phosphatase, catalase, chymotrypsin, N-acetyl-beta-glucosaminidase, beta-glucosidase,
beta-glucuronidase, alpha-mannosidase, nitrate reduction, pyrazinamidase, pyrrolidonyl arylamidase, trypsin, urease, acid
production from: amygdalin, L-arabinose, arbutin, gentibiose, inulin, 2-ketogluconate, lactose, mannitol, raffinose, salicin, sorbitol &
Variable results for esculin hydrolysis, acid production from: adonitol, dulcitol, glycogen, mannose, melibiose, melezitose, starch,
sucrose (saccharose), rhamnose, ribose, trehalose & turanose.
(c) Costin Stoica