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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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All of the following pathogenic bacteria fulfill Koch's postulates, except?
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The correct answer is  According to Koch's postulate: it must be possible to isolate a bacterium from the site of lesion and grow it in a cell-free culture medium. Pathogenic Treponemes do not grow in a cell-free aificial culture medium. Ref: Textbook of Microbiology; Ananthanarayan and Paniker; 9th edition; Pg no: 370