Francisella

(microbiology) A genus of gram-negative, aerobic bacteria of uncertain affiliation; cells are small, coccoid to ellipsoidal, pleomorphic rods and can be parasitic on mammals, birds, and arthropods.

A genus of very small, coccoid to ellipsoidal, pleomorphic, nonmotile and nonsporulating, gram-negative, rod-shaped bacteria. Fastidious and strictly aerobic, it grows at 98.6°F (37°C) within several days, but only in enriched media such as coagulated egg yolk or glucose-cysteine-blood-agar. The organisms occur in natural waters of the Northern Hemisphere, and can be parasitic and pathogenic in birds, anthropods, and mammals, including humans. Francisella tularensis has been found in many wild animals throughout North America, continental Europe, and Asia. Tularemia in humans is acquired via transmission by blood-sucking arthropods or by contact with infected animals, most frequently by hunters and butchers. See also Antibiotic; Medical bacteriology; Tularemia.

A type of gram-negative eubacteria with cell walls. It requires oxygen to survive.

A genus of coccoid or rod-shaped, gram-negative aerobic bacteria, having some pathogenic species.