Inveed fir tree appearance on gelatin stab is characteristic of?
Virulent capsulated strains of Bacillus anthracis form rough culture, while avirulent or attenuated strains form smooth colonies. on gelatin stab culture, a characteristic 'inveed fir tree' appearance is seen with slow liquefaction commencing from the top. On blood agar the colonies are nonhemolytic though occasional strains produce a narrow zone of hemolysis .in broth growth occurs as floccular deposits with little or no turbidity REF:Ananthanarayan & Panicker's Textbook of Microbiology 8th Edition pg no: 243
Mycoplasma
Bacillus anthracis
Clostridium
Bacteriodes
general microbiology