22 Mobilization and Oxidation of Fatty Acids Flashcards
purpose of B-oxidation
to generate energy in ATP, from the oxidation of fatty acids during fasting
products of B-oxidation
1 FAD(H)2, 1 NADH, 1 Acetyl CoA, and Fatty acyl CoA that’s 2 carbons shorter
B-oxidation in a nutshell and what it involves
the breakdown of fatty acyl CoA to Acetyl CoA by removing 2 carbons at a time,
involves fatty acid activation and transport of fatty acylCoA from cytosol into mitochondrial matrix
fatty acid substrates for B-oxidation come from where?
these fatty acids mainly come from fat tissue stores (adipose tissue)
How do these fatty acid substrates get to the mitochondria
adipose tissue TAGs release FAs, and transport to tissues bound to albumin. once at cells, FA binding protein transports FAs across plasma membrane and binds to them in cytosol. Activated Fatty acyl
How are Fatty acyl CoAs, activated fatty acids, transported across the cytosol to the mitochondrial matrix?
NLL
last round of B-oxidation in even chain fatty acids (typical ones)
yields a 4 carbon Fatty acyl CoA, butyryl CoA, Its cleavage produces 2 Acetyl CoA, both 2 carbons
last round of B-oxidation in odd chain fatty acids
yields a 5 carbon Fatty acyl CoA, its cleavage produces Propionyl CoA, a 3 carbon molecule, and Acetyl CoA, a 2 carbon one.
what happens to propionyl CoA, product of odd chain fatty acid oxidation?
propionyl CoA is converted to succinyl CoA, used as an anaplerotic reaction for the TCA cycle or as a precursor for gluconeogenesis
tissues which don’t use fatty acids as fuel
the Brain does not, it prefers ketone bodies if it can’t get glucose, Red blood cells- don’t have mitochondria, and Adipose tissue, rely on glycolysis for energy, its main job is to store FAs as TAGs