This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Microbiology
[{'content': 'Streptococcus all are true except- \nSelect and explain. \nA. Streptodornase cleaves DNA, B. Streptolysis 0 is active in reduced state, C. Streptokinase is produced from serotype A,C,K, D. Pyrogenic toxin A is plasmid mediated', 'role': 'user'}, {'content': "Answer: D \nExplanation: Ans. is 'd' i.e., Pyrogenic toxin A is plasmid mediated Three toxin types of streptococcal pyroexotoxin have been identified : A, B and C. Type A and C are coded for bacteriophage genes, while type B gene is chromosomal. Streptolysin '0' is oxygen labile; therefore, it is active in reduced state only Streptokinase is also known as fibrinolysin. It is expressed on all strains of streptococcus pyogenes (including A,C,K). It is expressed close to plasminogen binding site on the bacterial surface, it is activated to plasmin by streptokinase. Deoxyribonucleases (streptodornases) hydrolyze nucleic acids (e.g. DNA).", 'role': 'assistant'}]