Which of the following statement regarding Nitric Oxide Synthase is TRUE?: (A) It is inhibited by Calcium, (B) It accepts electrons from NADH, (C) It catalyzes a dioxygenase reaction, (D) It requires NADPH, FAD, FMN and Heme iron
Answer is D. Nitric oxide synthase is an enzyme required for the synthesis of nitric oxide from arginine. It is a dimeric protein and contains heme, FAD, FMN, tetrahydrobiopterin and calmodulin. This enzyme utilises molecular oxygen and NADPH. Ref: Harper's Illustrated Biochemistry, 26th Edition, Page 572; Lippincott's Biochemistry, 2nd Edition, Page 85; Textbook of Biochemistry By D M Vasudevan, 3rd Edition, Page 178