Statins work to inhibit cholesterol synthesis by competing for the active site of an enzyme involved in this pathway. What is the normal product of this enzyme?
a. Squalene
b. Mevalonate
c. HMG CoA
d. Isopenetnyl pyrophosphate
Answer: correct option is (b)
Mevalonate (the normal product formed in the cholesterol biosynthetic pathway or mevalonate pathway, by making conversions from HMG-CoA to mevalonic acid catalyzed by the enzyme HMG-CoA reductase)
Explanation: Statins are a group of drugs that are prescribed for treating the high cholesterol problems. This works by inhibiting the enzyme called HMG-CoA (hydroxymethylglutaryl-coenzyme A) reductase, this is the main enzyme involved in the cholesterol biosynthetic pathway. Mode of action offered by statins is via blocking the active sites present on the rate-limiting enzyme i.e., HMG-CoA reductase in the mevalonate pathway. This ultimately does not form the normal product called mevalonic acid and interferes with blocking the conversions made by the enzyme HMG-CoA to mevalonic acid.
Statins work to inhibit cholesterol synthesis by competing for the active site of an enzyme involved...
Answer the following two questions. Statins, such as lovastatin. competitively inhibit one of the enzymes of cholesterol synthesis. The structure of lovastatin is given below. Which enzyme does it inhibit? smallcircle HMG-CoA synthase smallcircle HMG-CoA reductase smallcircle pyrophosphomevalonate decarboxylase smallcircle squalene synthase
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HMG-CoA reductase, a critical enzyme in cholesterol synthesis is the target or statin inhibitors. You are characterizing a possible new inhibitor and want to determine its mode of binding to HMG-CoA reductase. Equilibrium dialysis measurements at 25 C, 30°C, and 37 C yielded dissociation constants (K.) of 2.5 x 10" М, 1.5 x 10", and 1.0 x 103 M, respectively, for the HMG-CoA reductase-inhibitor complex. a. Is the binding becoming better or worse with increasing temperature? Explain. b. Using Excel...
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