'Inveed fir tree' appearance is characteristic of?
B anthracis has a tendency to form very long chains of rods and in culture it is nonmotile and nonhemolytic. Colonies are characterized by a rough, uneven surface with multiple curled extensions at the edge resembling a "Medusa head." B anthracis has a D-glutamic acid polypeptide capsule of a single antigenic type that has antiphagocytic propeies. B anthracis endospores are extremely hardy and have been shown to survive in the environment for decades. On gelatin stab culture a characteristic inveed fir tree appearance is seen, with slow liquefaction commencing from top. Ref: Ray C.G., Ryan K.J. (2010). Chapter 26. Corynebacterium, Listeria, andBacillus. In C.G. Ray, K.J. Ryan (Eds), Sherris Medical Microbiology, 5e.
Bacillus anthracis
Haemophilus influenza
Yersinia pestis
Brucella