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: Biochemistry
[{'content': 'Which of the following enzyme is responsible for respiratory burst in neutrophils? \nSelect and explain. \nA. NADPH oxidase, B. Dehydrogenase, C. Peroxidase, D. Catalase', 'role': 'user'}, {'content': "Answer: A \nExplanation: When stimulated by contact with bacteria, neutrophils exhibit a respiratory burst and produce superoxide in a reaction catalyzed by NADPH oxidase. Also know: Superoxide (, hydrogen peroxide (H2O2), peroxyl radicals (ROO*), and hydroxyl radicals (OH*) and are referred to as reactive oxygen species (ROS). Superoxide is formed in the red blood cell by the autoxidation of hemoglobin to methemoglobin; in other tissues, it is formed by the action of enzymes such as cytochrome P450 reductase and xanthine oxidase. Superoxide can release iron ions from ferritin. Ref: Murray R.K. (2011). Chapter 52. Red & White Blood Cells. In D.A. Bender, K.M. Botham, P.A. Weil, P.J. Kennelly, R.K. Murray, V.W. Rodwell (Eds), Harper's Illustrated Biochemistry, 29e.", 'role': 'assistant'}]