Enterococcus spp. are best described as which type of organisms?

• A. Gram-negative rods that form spores
• B. Gram-positive bacilli that form long chains
• C. Facultative gram positive cocci, grow in short chains
• D. Anaerobic cocci in clusters

Answer: (C)

Enterococcus species are Gram-positive cocci that are facultative anaerobes. In lab specimens they appear as small round cells that typically arrange in short chains or sometimes in pairs, not in long chains or clusters. They are not Gram-negative, nor are they spores formers, and they are not strictly anaerobic. Their ability to grow with or without oxygen, along with their tendency to form short chains and their Gram-positive cocci morphology, is what distinguishes them from other bacteria described in the other options.