Malonyl CoA plays a key role in chain elongation in fatty acid biosynthesis.
It provides 2-carbon units to fatty acids and commits them to fatty acid chain synthesis.
Malonyl-CoA is formed by carboxylating acetyl-CoA using the enzyme acetyl-CoA carboxylase. One molecule of acetyl-CoA joins with a molecule of bicarbonate, requiring energy rendered from ATP.
Malonyl-CoA is utilised in fatty acid biosynthesis by the enzyme malonyl coenzyme A:acyl carrier protein transacylase (MCAT). MCAT serves to transfer malonate from malonyl-CoA to the terminal thiol of holo-acyl carrier protein (ACP).
Malonyl-CoA is a highly regulated molecule in fatty acid synthesis; as such, it inhibits the rate-limiting step in beta-oxidation of fatty acids. Malonyl-CoA inhibits fatty acids from associating with carnitine by regulating the enzyme carnitine acyltransferase, thereby preventing them from entering the mitochondria, where fatty acid oxidation and degradation occur.
How does malonyl-CoA effect fatty acid oxidation? Why is this important?
In the liver, which of the following enzymes is inhibited by malonyl CoA? A: fatty acid synthase, B: Acetyl CoA carboxylase, C: CPT-1, D: Hormone sensitive lipase
An activated fatty acid (acyl-CoA) can be transported into the mitochondria for b-oxidation or remain in the cytosol for lipogenesis to produce a triacylglycerol. What regulates the fate of this acyl-CoA? A. the amount of acyl-CoA in the mitochondria B. the amount of acyl-carnitine in the mitochondria C. the amount of NADH in the cytoplasm D. the amount of malonyl CoA in the cytoplasm E. the amount of acetyl-CoA in the cytoplasm
1. Describe the regulation of fatty acid oxidation and to relate this to cellular needs. Describe the role of malonyl–CoA in the regulation of fatty acid oxidation.
Question 1. Calculate the numbers of acetyl-CoA molecules produced when a fatty acid with 14 carbons after undergoing beta-oxidation? Question 2. How many a) cycles of beta-oxidation will a fatty acid with 14 carbons undergo? Explain briefly. b)? How many acetyl-CoA molecules ? explain briefly? Question 3. Consider the synthesis of fatty acids: Answer the flowing: True or False: a) CoA carries intermediate b) Acetyl-CoA donates two carbon atoms c) Malonyl-CoA donates two carbon atoms d) The reverse of fatty...
You have made malonyl-CoA from marked CO2 and unmarked acetyl-CoA. Then you are using this malonyl-CoA to synthetized a C12:0 fatty acid. The final product will be radioactive at which carbons?
A fatty acid composed of 20 carbon atoms undergoes β‑oxidation. How many acetyl CoA, FADH2, and NADH does β‑oxidation of this fatty acid generate? (answer is 10 acetyl CoA, 9 FADH2, 9 NADH) Calculate the net ATP generated by the β‑oxidation of the 20‑carbon fatty acid. Assume that each FADH2 generates 1.5 ATP and each NADH generates 2.5 ATP. number of ATP molecules: ??????
Stage 2: Fatty Acid Degradation to Acetyl CoA (The Fatty Acid Cycle, aka "B-Oxidation") 1. In the space below, draw the reaction for the activation of palmitic acid, a saturated 16-carbon fatty acid. 2. In the space below, fill in the structure for the reactant acyl CoA and draw all of the products that result from one turn of the fatty acid cycle. Is this reaction an oxidation or a reduction? 3. Besides fatty acid oxidation, glycerol (the other product of triglyceride digestion)...
What changes in fatty acid metabolism would result from a mutation in the muscle carnitine acyltransferase I in which the mutant protein has lost its affinity for malonyl-CoA but not its catalytic activity? A. Fatty acid synthesis in the mitochondria and fatty acid oxidation in the cytosol could occur simultaneously. B. Fatty acid synthesis in the cytosol and fatty acid oxidation in the mitochondria could occur simultaneously. C. Synthesis of malonyl carnitine could only occur at high malonyl-CoA concentration. D....
How does oxidation of a saturated fatty acid differ from the oxidation of an unsaturated fatty acid?
EOS Fatty acid metabolism: Q1 1 point possible (graded) Fatty acid synthase is primed with two molecules at the beginning of odd-chain fatty acid synthesis. What are these TWO molecules? Propionyl-COA Palmitoyl-CoA Malonyl-CoA Acetyl-COA I Acyl-Coa union How many molecules of malonyl-CoA would be invested to synthesize one molecule of the fatty acid shown above? How many molecules of NADPH would be invested to synthesize one molecule of the fatty acid shown above? How many molecules of ATP would be...