|Enterococcus faecalis colonies on Sheep Blood Agar
|E. faecalis. Gram-positive ovoid cocci, short chains
Phylum Firmicutes, Class Bacilli, Order Lactobacillales, Family Enterococcaceae, Genus Enterococcus, Enterococcus faecalis
(Andrewes and Horder 1906) Schleifer and Kilpper-Bälz 1984, type species of the genus. Lancefield group D.
Basonym: Streptococcus faecalis Andrewes and Horder 1906.
Historical synonyms: Micrococcus ovalis Escherich 1886, Streptococcus liquefaciens Sternberg 1892, Micrococcus zymogenes
MacCallum and Hastings 1899, "Enterocoque" Thiercelin 1902, Enterococcus proteiformis Thiercelin and Jouhaud 1903,
Streptococcus glycerinaceus Orla-Jensen 1919.
Gram-positive, ovoid cells elongated in the direction of the chain, occur singly, in
pairs, or in short chains. Usually non-motile.
Colonies on blood agar or nutrient agar are circular, smooth, and entire. Most strains
are nonhemolytic; rarely, strains exhibit beta-hemolysis. Strains grow at 10 and 45 ºC,
survive heating at 60 ºC for 30 min, and grow in 6.5% NaCl at pH 9.6 and in 0.1%
methylene blue milk. Aerobic, facultatively anaerobic. Growth occurs in the presence
of 0.04% tellurite, and in the presence of 0.01% tetrazolium (form red colonies).
Growth occurs in the presence of 0.1% thallous acetate and 0.02% sodium azide.
Does not require folic acid for growth.
Isolated from feces & gastrointestinal tract of humans and animals including
mammals, birds, insects, and reptiles. E. faecalis represents the most commonly
isolated enterococcal species from human clinical material (80–90%). Isolated also
from rectum and tonsils of dogs and cats, from plants, crustaceans, soil and
Can contaminate carcasses, milk and dairy products during processing.
Normal inhabitant of the human and animal intestine, may produce nosocomial
- Pavel Svec and Luc A. Devriese, 2009: Genus I. Enterococcus (ex Thiercelin and Jouhaud 1903) Schleifer and Kilpper-Bälz 1984,
32VP in Bergey’s Manual of Systematic Bacteriology, Second Edition, Volume Three, Vos, P.D.; Garrity, G.; Jones, D.; Krieg, N.R.;
Ludwig, W.; Rainey, F.A.; Schleifer, K.-H.; Whitman, W.B. (Eds.), pp 594-606.
- Karl H. Schleifer and Renate Kilpper-Balz. Transfer of Streptococcus faecalis and Streptococcus faecium to the Genus
Enterococcus nom. rev. as Enterococcus faecalis comb. nov. and Enterococcus faecium comb. nov. Int J Syst Bacteriol January
1984 34:31-34; doi:10.1099/00207713-34-1-31.
Some strains produce a pseudocatalase.
Positive results for Voges-Proskauer, hydrolysis of hippurate, hydrolysis of esculin,
pyrrolidonylarylamidase, arginine dihydrolase, acid production from: glycerol,
mannitol, sucrose, trehalose, D-tagatose, ribose, galactose, D-glucose, D-fructose,
D-mannose, N-acetylglucosamine, salicin, cellobiose, maltose, lactose,
beta-gentiobiose, amygdalin & arbutin. Utilize pyruvate, citrate, malate & serine.
Negative results for alpha-galactosidase, beta-glucuronidase, beta-galactosidase,
alkaline phosphatase, acid production from: erythritol, D-arabinose, L-arabinose,
alpha-methyl-xyloside, inositol, D-fucose, L-fucose , D- & L- xylose, adonitol,
L-sorbose, dulcitol, alpha-methyl-D-mannoside, alpha-methyl-D-glucoside,
melibiose, inulin, D-raffinose, glycogen, xylitol, D-turanose, D-lyxose, D- or L-arabitol
Variable results for acid production from: rhamnose, sorbitol, melezitose, starch,
gluconate & 2-ketogluconate.
(c) Costin Stoica