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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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Bacteria aquires restriction endonuclease by horizontal transfer. The result would be -
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The correct answer is  Any bacteria is protected against its own RE by a companion enzyme, site-specific DNA methylase, which methylates the restriction sites recognised by that particular RE. If any bacteria acquire new RE by horizontal transfer, this RE will cleave bacterial DNA and kill bacteria.