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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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Beta phage is seen in
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The correct answer is  The toxigenicity of the diphtheria bacillus depends on the intracellular presence of corynephages (tox+), which acts as genetic controlling toxin production. Non-toxigenic strains are rendered toxigenic by infecting them with the beta or some other phages This is known as lysogenic or phage conversion. REF:Textbook of microbiology; Ananthanarayan and paniker's; 10th Edition; Pg: 240