Lipid Synthesis Enzymes - Biochemistry

Because acetyl-CoA Carboxylase (ACC) is directly responsible for synthesis of malonyl-CoA, inhibiting it would be the most targeted approach. Inhibiting acyl-CoA dehydrogenase or pyruvate dehydrogenase would decrease available acetyl-CoA to ACC by inhibiting beta-oxidation and conversion of pyruvate to acetyl-CoA, but this would have a large impact on other biosynthetic pathways as well, due to the ubiquity of acetyl-CoA.

-hydroxybutyrate dehydrogenase catalyzes the interconversion of the ketone bodies acetoacetate and -hydroxybutyrate, which are transported out of liver cells into the blood to be used as fuel by the rest of the body, particularly during times of starvation. -hydroxybutyrate dehydrogenase’s only coenzyme is . As for the other answers: the pyruvate dehydrogenase complex converts pyruvate into acetyl-CoA, the key connection between glycolysis and the citric acid cycle, and this process uses a number of co-factors, including , thiamine pyrophosphate, lipoamide (the protein-bound form of lipoic acid), and, of course, coenzyme A (to make acetyl-CoA). Pyruvate dehydrogenase uses and depending on the cell type.

The endogenous, not the exogenous, pathway, involves the transformation of VDLDs into LDLs. Meanwhile, the exogenous, not the endogenous, pathway, involves transforming chylomicrons into remnants. The apolipoprotein in plasma (transporting cholesterol to the liver) which is the major component of HDL is A1, not B100. Macrophages do indeed oxidize LDLs and transform themselves into the foam cells which indicate atherosclerosis. This is one of the reasons that LDL cholesterol levels can indicate atherosclerosis (which is associated with increased risk of heart attack or stroke).

Acyl-Carrier Protein (ACP) is a protein that is important to the generation of lipids. Specifically, it aids in the production of fatty acids. Furthermore, ACP is just one component of the Fatty Acid Synthase enzyme, which is devoted to the synthesis of fatty acids.

To begin the process, ACP is first activated by having an acetyl-CoA molecule attached to it. Next, a compound called malonyl-CoA is attached to the bound acetyl-CoA. Malonyl-CoA is a three carbon compound, but upon being added to the acetyl-CoA, the malonyl-CoA becomes decarboxylated. The importance of this is that by producing carbon dioxide as a product, this helps to greatly drive the reaction forward.

Keep in mind that there are other chemical transformations happening when these malonyl-CoA molecules are being "stitched" together. Every time a malonyl-CoA is added, the carbon chain becomes increased by two more carbons. This keeps happening until, finally, a fatty acid is generated.

Lecithin-cholesterol acyltransferase-LCAT adds a fatty acid to cholesterol, which can then be loaded onto high-density lipoproteins. Without the enzyme, cholesterol does not get to be transported by high density lipoproteins to the liver. Cholesterol then accumulates in tissue such as the eye and renal tissue. LCAT does impact cholesterol transport. Lipoprotein lipase is the enzyme that hydrolyzes fatty acids from triglycerides and cholesterol. Fatty acid synthase converts malonyl-CoA into palmitate. Acetyl-CoA carboxylase is the enzyme that incorporates acetyl-CoA into fatty acids.

Fatty acid desaturases are located on the endoplasmic reticulum and convert saturated fatty acids to unsaturated fatty acids by producing double bonds. The enzymes have a N-terminal cytochrome b5-like domain. Arachidonic acid is a highly unsaturated fatty acid.

Citrate crosses the mitochondrial matrix into the cytosol and is converted into acetyl-CoA and oxaloacetate by citrate lyase during fatty acid synthesis, as part of the citrate shuttle. The process requires hydrolysis of energy-rich ATP bonds.

The role of fatty acid synthase is to synthesize fatty acids,more specifically to convert acetyl-CoA, malonyl-CoA, and NADPH to palmitate (a fatty acid) and NADP. It is a multienzyme complex consisting of 7 components: acetyl CoA-ACP transacetylase, malonyl-CoA-ACP transacetylase, Beta-ketoacyl synthase, Beta-ketoacyl reductase, Beta-hydroxyacyl dehydratase, enoyl reductase, thioesterase.

The DH subunit is a dehydratase, meaning it removes alcohol groups from carbon chains. If this subunit is mutated, the alcohol cannot be removed.

Because acetyl-CoA Carboxylase (ACC) is directly responsible for synthesis of malonyl-CoA, inhibiting it would be the most targeted approach. Inhibiting acyl-CoA dehydrogenase or pyruvate dehydrogenase would decrease available acetyl-CoA to ACC by inhibiting beta-oxidation and conversion of pyruvate to acetyl-CoA, but this would have a large impact on other biosynthetic pathways as well, due to the ubiquity of acetyl-CoA.

-hydroxybutyrate dehydrogenase catalyzes the interconversion of the ketone bodies acetoacetate and -hydroxybutyrate, which are transported out of liver cells into the blood to be used as fuel by the rest of the body, particularly during times of starvation. -hydroxybutyrate dehydrogenase’s only coenzyme is . As for the other answers: the pyruvate dehydrogenase complex converts pyruvate into acetyl-CoA, the key connection between glycolysis and the citric acid cycle, and this process uses a number of co-factors, including , thiamine pyrophosphate, lipoamide (the protein-bound form of lipoic acid), and, of course, coenzyme A (to make acetyl-CoA). Pyruvate dehydrogenase uses and depending on the cell type.

The endogenous, not the exogenous, pathway, involves the transformation of VDLDs into LDLs. Meanwhile, the exogenous, not the endogenous, pathway, involves transforming chylomicrons into remnants. The apolipoprotein in plasma (transporting cholesterol to the liver) which is the major component of HDL is A1, not B100. Macrophages do indeed oxidize LDLs and transform themselves into the foam cells which indicate atherosclerosis. This is one of the reasons that LDL cholesterol levels can indicate atherosclerosis (which is associated with increased risk of heart attack or stroke).

Acyl-Carrier Protein (ACP) is a protein that is important to the generation of lipids. Specifically, it aids in the production of fatty acids. Furthermore, ACP is just one component of the Fatty Acid Synthase enzyme, which is devoted to the synthesis of fatty acids.

To begin the process, ACP is first activated by having an acetyl-CoA molecule attached to it. Next, a compound called malonyl-CoA is attached to the bound acetyl-CoA. Malonyl-CoA is a three carbon compound, but upon being added to the acetyl-CoA, the malonyl-CoA becomes decarboxylated. The importance of this is that by producing carbon dioxide as a product, this helps to greatly drive the reaction forward.

Keep in mind that there are other chemical transformations happening when these malonyl-CoA molecules are being "stitched" together. Every time a malonyl-CoA is added, the carbon chain becomes increased by two more carbons. This keeps happening until, finally, a fatty acid is generated.

Lecithin-cholesterol acyltransferase-LCAT adds a fatty acid to cholesterol, which can then be loaded onto high-density lipoproteins. Without the enzyme, cholesterol does not get to be transported by high density lipoproteins to the liver. Cholesterol then accumulates in tissue such as the eye and renal tissue. LCAT does impact cholesterol transport. Lipoprotein lipase is the enzyme that hydrolyzes fatty acids from triglycerides and cholesterol. Fatty acid synthase converts malonyl-CoA into palmitate. Acetyl-CoA carboxylase is the enzyme that incorporates acetyl-CoA into fatty acids.

Fatty acid desaturases are located on the endoplasmic reticulum and convert saturated fatty acids to unsaturated fatty acids by producing double bonds. The enzymes have a N-terminal cytochrome b5-like domain. Arachidonic acid is a highly unsaturated fatty acid.

Citrate crosses the mitochondrial matrix into the cytosol and is converted into acetyl-CoA and oxaloacetate by citrate lyase during fatty acid synthesis, as part of the citrate shuttle. The process requires hydrolysis of energy-rich ATP bonds.

The role of fatty acid synthase is to synthesize fatty acids,more specifically to convert acetyl-CoA, malonyl-CoA, and NADPH to palmitate (a fatty acid) and NADP. It is a multienzyme complex consisting of 7 components: acetyl CoA-ACP transacetylase, malonyl-CoA-ACP transacetylase, Beta-ketoacyl synthase, Beta-ketoacyl reductase, Beta-hydroxyacyl dehydratase, enoyl reductase, thioesterase.

The DH subunit is a dehydratase, meaning it removes alcohol groups from carbon chains. If this subunit is mutated, the alcohol cannot be removed.

Because acetyl-CoA Carboxylase (ACC) is directly responsible for synthesis of malonyl-CoA, inhibiting it would be the most targeted approach. Inhibiting acyl-CoA dehydrogenase or pyruvate dehydrogenase would decrease available acetyl-CoA to ACC by inhibiting beta-oxidation and conversion of pyruvate to acetyl-CoA, but this would have a large impact on other biosynthetic pathways as well, due to the ubiquity of acetyl-CoA.