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Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
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Inveed fir tree appearance on gelatin stab is characteristic of?
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The correct answer is  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