Term
| What is the classification for fatty acid with a chain length >C20? |
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Definition
| very-long-chain length fatty acids |
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Term
| What is the classification for fatty acid with a chain length C12-C20? |
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Definition
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Term
| What is the classification for fatty acid with a chain length C6-C12? |
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Definition
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Term
| What is the classification for fatty acid with a chain length C4? |
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Definition
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Term
| Long-chain fatty acids circulate through the blood bond to? |
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Definition
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Term
| What converts long-chain fatty acids to fatty acyl coenzyme A (fatty acyl CoA)? |
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Definition
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Term
| An activated acyl group is transported into the mitochondrial matrix bound to? |
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Definition
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Term
| In the Beta-oxidation pathway, fatty acid is oxidized to? |
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Definition
1 FAD(2H)
1 NADH
1 acetyl CoA |
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Term
| What are two ketone bodies (acetyl CoA generated from fatty acid oxidation is converted to this)? |
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Definition
1) acetoacetate
2) B-hydroxybutyrate |
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Term
| What fatty acid type metabolism does not require carnitine and this metabolism occurs only in the liver? |
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Definition
| water soluble medium-chain length fatty acids |
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Term
| Odd-chain length fatty acids undergo B-oxidation to? |
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Definition
| the terminal three-carbon propionyl CoA |
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Term
| What happens to propionyl CoA? |
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Definition
| It enters the TCA cycle as succinyl CoA. |
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Term
| Excess fatty acids might undergo this? |
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Definition
| omega(w)-oxidation- converts them to dicarboxylic acids which appear in the urine |
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Term
| How are very-long-chain length fatty acids(both straight-chain and branched fatty acids) are whittled down to size by? |
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Definition
| peroxisomal alpha and beta oxidation |
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Term
| What are the products of peroxisomal alpha and beta oxidation? |
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Definition
| H2O2, NADH, acetyl CoA or propionyl CoA and medium-chain or shirt-chain fatty acids |
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Term
| Can the liver use ketone bodies for fuel? |
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Definition
| No, it only can synthesize them |
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Term
| What inhibits formation of the fatty acyl carnitine derivatives? |
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Definition
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Term
| What are the major fatty acids that are oxidized? |
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Definition
| palmitate(C16), oleate(C18:1), and stearate(C18) |
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Term
| What can activate lipolysis? |
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Definition
| glucagon and other insulin counter-regulatory enzymes-(eg- epinephrine and norepinephrine) |
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Term
| What is the structure of linoleate? |
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Definition
| C18:2- polyunsaturated essential fatty acid |
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Term
| What contains principally saturated and monounsaturated long-chain fatty acids? |
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Definition
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Term
| What contain linoleate and some longer-chain and polyunsaturated fatty acids? They also contain smaller amounts of branched-chain and odd-chain-length fatty acids. |
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Definition
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Term
| What contains medium-chain length fatty acids? |
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Definition
| dairy fat, maternal milk, and vegetable oils |
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Term
| Fatty acids synthesis generates? |
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Definition
| palmitate(C16)-its from excess calories ingested as glucose |
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Term
| Palmitate can be elongated to form? |
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Definition
| stearate(C18) and oleate(C18:1) |
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Term
| What are toxic to cells because they can disrupt the hydrophobic bonding between amino acid side chains in proteins? |
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Definition
| long-chain fatty acids(cause they are hydrophobic and water insoluble)- thus they are transported in the blood bound to proteins such as albumin |
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Term
| What releases long-chain fatty acids from adipose tissue triacylclycerols? |
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Definition
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Term
| Fatty acids enter cell by two pathways... |
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Definition
1) saturable transport process
2) diffusion through the lipid plasma membrane |
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Term
| What enzyme activates long-chain fatty acids for B-oxidation by using ATP energy to form the fatty acyl CoA thioester bond? In this reaction, the B-bond of ATP is cleaved to form a fatty acyl AMP intermediate and pyrophosphate (PPi). Subsequent cleavage of PPi helps to drive the reaction. |
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Definition
| acyl CoA synthetase (thiokinase) |
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Term
| Where is acyl CoA synthetase located? |
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Definition
1) endoplasmic reticulum
2) outer mitochondrial membranes
3) peroxisomal membranes |
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Term
| What is the the most common of these diseases, is characterized by adolescent to adult onset of recurrent episodes of acute myoglobinuria precipitated by prolonged exercise or fasting? During these episodes, the patient is weak, and may be somewhat hypoglycemic with diminished ketosis (hypoketosis), but metabolic decompensation is not severe. Lipid deposits are found in skeletal muscles. CPK levels, and long-chain acylcarnitines are elevated in the blood. |
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Definition
This disease is carnitine acyltransferase II or CPT II deficiency.
CPTII levels in fibroblasts are approximately 25% of normal. The remaining CPTII activity probably accounts for the mild effect on liver metabolism. In contrast, when CPTII deficiency presents in infants, CPT II levels are <10% of normal, the hypoglycemia and hypoketosis are severe, hepatomegaly occurs from the triacylglycerol deposits, and cardiomyopathy is also present. |
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Term
| What are able to reversibly transfer an activated fatty acyl group from CoA to the hydroxyl group of carnitine to form an acylcarnitine ester? |
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Definition
| Carnitine acyl transferase- The reaction is reversible,so the fatty acyl CoA derivative can be regenerated from the carnitine ester. |
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Term
| What is the enzyme that transfers long-chain fatty acyl groups from CoA to carnitine; it is located on the outer mitochondrial membrane? |
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Definition
| Carnitine:palmitoyltransferase I (CPTI) |
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Term
| What helps fatty acylcarnitine cross the inner mitochondrial membrane? |
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Definition
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Term
| The fatty acyl group is transferred back to CoA by a second enzyme? |
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Definition
| Carnitine:palmitoyltransferase II (CPTII) |
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Term
| What is obtained in the diet or it can be synthesized from the side chain of lysine? |
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Definition
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Term
| How many types of reactions occur in Beta-oxidation? |
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Definition
4
1) acyl CoA Dehydrogenase
2) enoyl hydratase
3) hydroxyacyl CoA Dehydrogenase
4) B-ketothiolases |
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Term
| In the first reaction in B-oxidation, a double bond is formed between the B- and a- carbons by this enzyme? What else is produced during this rxn? |
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Definition
| acyl CoA Dehydrogenase- produces a FAD(2H) |
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Term
| The second step in B-oxidation, an -OH from water is added to the B-carbon, and an –H from water is added to the a-carbon by this enzyme? |
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Definition
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Term
| In the third step of B-oxidation,the hydroxyl group on the B-carbon is oxidized to a ketone by? What is also formed during this step? |
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Definition
| hydroxyacyl CoA dehydrogenase- NADH is produced |
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Term
| In the fourth B-oxidation reaction, the bond between the B- and a-carbons is cleaved by a reaction that attaches CoASH to the B-carbon, and acetyl CoA is released? |
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Definition
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Term
| What moves the double bond from the 3,4-position so that it is trans and in the 2,3-position,and B-oxidation continues? This is necessary for unsaturated fatty acids. |
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Definition
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Term
| What regulates B-oxidation in general? |
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Definition
| free CoASH, availability of NAD+, and FAD |
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Term
| What is is synthesized in the cytosol of many tissues by acetyl CoA carboxylase? It inhibits CPTI. |
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Definition
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Term
| What results from defective peroxisomal biogenesis, leads to complex developmental and metabolic phenotypes that affect principally the liver and the brain. One of the metabolic characteristics of these diseases is an elevation of C26:0 and C26:1 fatty acid levels in plasma. |
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Definition
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Term
| What disease is caused by a deficiency in a single peroxisomal enzyme, the phytanoyl CoA hydroxylase that carries out B-oxidation of phytanic acid. Symptoms include retinitis pigmentosa, cerebellar ataxia, and chronic polyneuropathy. Because phy-tanic acid is obtained solely from the diet, plac-ing patients on a low-phytanic acid diet hasresulted in marked improvement. |
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Definition
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Term
| What amino acids are called ketogenic amino acids because their carbon skeleton is catabolized to acetyl CoA or acetoacetyl CoA, which may enter the pathway of ketone body synthesis in liver? |
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Definition
| leucine(L), Isoleucine(I), Lysine(K), Tryptophan(W), Phenylalanine(P), and Tyrosine(Y) |
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Term
| What amino acids also form acetyl CoA and acetoacetyl CoA in other tissues as well as the liver? |
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Definition
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