All of the following enzymes catalyze a committed step except: A. HMG-CoA reductase B. Acetyl-CoA carboxylase...

All of the following enzymes catalyze a committed step except:
A. HMG-CoA reductase
B. Acetyl-CoA carboxylase
C. Fattyacyl-CoA synthetase

D. Pyruvate dehydrogenase complex
E. All of the above enzymes catalyze a committed step

Expert Solution

Answer: A. HMG-CoA reductase is an enzyme that catalyzes a rate limiting/committed step in mevalonate pathway. This enzyme catalyzes the conversion of HMG-CoA to mevalonic acid. Hence, the enzyme in option A catalyze committed step and is an incorrect answer

B. Acetyl-CoA carboxylase is an enzyme that catalyzes conversion of acetyl-CoA to malonyl-CoA, a rate limiting step in fatty acid biosynthesis. Hence, the enzyme in option B catalyze committed step and is an incorrect answer

C. Fatty acyl-CoA synthetase is an enzyme that is involved in the activation of fatty acid by forming a thioester bond between fatty acid and coenzyme A using ATP. This enzyme is an ligase and activates the fatty acid for oxidation. It is not a committed step in fatty acid oxidation and is the correct answer.

D. Pyruvate dehydrogenase complex consists of three enzyme pyruvate dehydrogenase (E1), dihydrolipoyl transacetylase (E2), and dihydrolipoyl dehydrogenase (E3). This complex converts pyruvate to acetyl-CoA. The step catalyzed by the enzyme pyruvate dehydrogenase (E1) of pyruvate dehydrogenase complex is a rate limiting step. Hence, the enzyme complex in option D catalyze committed step and is incorrect answer

gladiator answered 1 year ago

1. Acetyl CoA carboxylase . . . A. is activated by citrate B. is activated by...

1. Acetyl CoA carboxylase . . . A. is activated by citrate B. is activated by palmitate or palmitoyl SCoA C. is the rate-determining step of fatty acid breakdown D. B and C above E. A and B above 2. High density lipoproteins particles . . . A. transport endogenous lipids B. transport cholesterol from the liver to the tissues, predominantly C. A and B above D. None of the above above 3. Adipocytes . . . A. store large...

How does an HMG-CoA reductase inhibitor reduce cholesterol?

Explain the regulation of the allosteric enzyme acetyl-CoA carboxylase by citrate and palmitoyl-CoA.

1. List the select prototype medication for the HMG-CoA reductase inhibitors (statins).

1. List the select prototype medication for the HMG-CoA reductase inhibitors (statins).2. Describe myopathy. List the nursing actions and client education regarding myopathy.3. Heparin is the select prototype medication for parenteral anticoagulants. List 2 complications of heparin and give at least 2 nursing actions for each complication.4. What are the therapeutic uses for the oral anticoagulant warfarin?5. What are the therapeutic uses for Dabigatran?

What are the roles of the COENZYMES involved in HMG-CoA Reductase catalyzed cholesterol synthesis in humans.

1. List the select prototype medication for the HMG-CoA reductase inhibitors (statins). There is only one...

1. List the select prototype medication for the HMG-CoA reductase inhibitors (statins). There is only one prototype drug for this class. 2. Describe myopathy. List the nursing actions and client education regarding myopathy. 3. Heparin is the select prototype medication for parenteral anticoagulants. List 2 complications of heparin and give at least 2 nursing actions for each complication. 4. What are the therapeutic uses for the oral anticoagulant warfarin? 5. What are the therapeutic uses for Dabigatran?

HMG-CoA reductase is a highly regulated enzyme. Identify three distinct mechanisms by which this enzyme is...

HMG-CoA reductase is a highly regulated enzyme. Identify three distinct mechanisms by which this enzyme is regulated. For each, describe the triggering event and its outcomes on HMGR levels or activity.

Why is HMG-CoA reductase a target in attempts to lower plasma cholesterol levels and explain how...

Why is HMG-CoA reductase a target in attempts to lower plasma cholesterol levels and explain how lovastatin and cholestyramine work to lower blood cholesterol levels?

Statin drugs, like Mevacor (lovastatin) and Lipitor (atorvastatin), act as competitive inhibitors of HMG-CoA reductase by...

Statin drugs, like Mevacor (lovastatin) and Lipitor (atorvastatin), act as competitive inhibitors of HMG-CoA reductase by mimicking the structure of mevalonate. However, it is not this inhibition that directly lowers cholesterol levels in the blood. A) What enzymatic reaction does HMG CoA-reductase catalyze? What is important about this step of cholesterol synthesis? B) How can statins mechanistically cause a decrease in LDL cholesterol in the blood if it is not a direct effect of decreased cellular cholesterol synthesis?

Mrs. Morris’ physician has decided to prescribe an ACE inhibitor and an HMG-CoA reductase inhibitor (Zocor)....

Mrs. Morris’ physician has decided to prescribe an ACE inhibitor and an HMG-CoA reductase inhibitor (Zocor). Mrs. Morris’ labs have improved a little bit between 6/25 and 3/15, what would you attribute to Zocor use?

Question