Gram+ cocci in pairs or short chains.

Note: Enterococci used to be known as Group D Streptococci, so it makes sense they look like strep.

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White, alpha-hemolytic colonies. They can tolerate extreme conditions including high temperature, salt, and bile. They also hydrolyze escalin, and thus turn bile escalin agar black.

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They are part of the normal flora of the GI tract.

No known classic virulence factors. Instead, Entercoccus is an opportunistic pathogen, growin when competing flora and cleared (by antibiotics). Often found in:

-- Mixed infection wounds (e.g. diabetic ulcer)

-- UTIs

-- Endocarditis

Note: One of the top causes of nosocomial infection.

Must use multiple, synergistic antibiotics. 

Enterococci are inherently resistant to many drugs, including:

-- sulfonamides (usually)

-- tetracyclines (ofen)

-- erythromycin, chloamphenicol (occasionally)

-- penicillins (bacteriostatic at typical doses)

-- aminoglycosides (penetrate cell wall poorly)

Note: Acquiring resistance to vancomycin; vancomycin-resistant strains found in pig farms

Horizontal gene transfer. Insertion sequence IS16 increased genomic plasticity, facilitating later acquisition of cassette proteins conferring antibiotic resistance.

Multidrug resistance and ability to tolerate extreme environments, not because of any virulence factor(s).