Beta Oxidation

Each list begins with basic conceptual vocabulary you need to know for MCAT questions and proceeds to advanced terms that might appear in context in MCAT passages. The terms are links to Wikipedia articles.
Lipolysis
Lipolysis is the metabolic pathway through which lipid triglycerides are hydrolyzed into a glycerol and three fatty acids.
Very-low-density
Very-low-density lipoproteins transport endogenous triglycerides, phospholipids, cholesterol, and cholesteryl esters, functioning as the body's internal transport mechanism for lipids.
Chylomicrons
Chylomicrons, also known as ultra low-density lipoproteins (ULDL), are lipoprotein particles that consist of triglycerides (85–92%), phospholipids (6–12%), cholesterol (1–3%), and proteins (1–2%).
Carnitine
In support of energy metabolism, carnitine transports long-chain fatty acids into mitochondria to be oxidized for energy production, and also participates in removing products of metabolism from cells.
Beta oxidation
Beta oxidation is the process by which fatty acids, in the form of Acyl-CoA molecules, are broken down in the mitochondria and/or in peroxisomes to generate Acetyl-CoA, the entry molecule for the Krebs Cycle.
Ketosis
Ketosis is a stage in metabolism occurring when the liver converts fat into fatty acids and ketone bodies which can be used by the body for energy.
Mitochondrial trifunctional protein
Mitochondrial trifunctional protein (MTP) is a protein attached to the inner mitochondrial membrane which catalyzes three out of the four steps in beta oxidation.
Ketone bodies
Ketone bodies are three water soluble compounds that are produced as by-products when fatty acids are broken down for energy. They are used as a source of energy in the heart and brain.
Thiolysis
Thiolysis is a reaction with a thiol (R-SH) that cleaves one compound into two.
Long chain fatty acyl-CoA ligase
The long chain fatty acyl-CoA ligase is an enzyme that activates the oxidation of complex fatty acids through formation of fatty acyl-CoA by a two-step process proceeding through an adenylated intermediate.
Acyl CoA dehydrogenase
Acyl CoA dehydrogenase is the enzyme used to catalyze the first step of beta-oxidation in fatty acid metabolism.
Enoyl-CoA hydratase
Enoyl-CoA hydratase is the enzyme used to catalyze the second step of beta-oxidation in fatty acid metabolism.
3-Hydroxyacyl CoA dehydrogenase
The third step of beta oxidation in fatty acid metablism is the oxidation of L-3-hydroxyacyl CoA by NAD+, which is catalyzed by 3-Hydroxyacyl CoA dehydrogenase.
Thiolase
The final step of beta oxidation in fatty acid metablism is the cleavage of 3-ketoacyl CoA by the thiol group of another molecule of CoA, which is catalyzed by Acetyl-CoA C-acyltransferase, also known as thiolase.




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