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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.
user
Carrom coin appearance of pneumococcus is due to
assistant
The correct answer is  Autolysin is amidase enzyme that cleaves peptidoglycan leading to autolysis of cells. 
This property is responsible for carrom coin appearance of pneumococcal colonies.