- high-resolution terminology - matching measurements at high-resolution
Fatty acid oxidation
Description
Fatty acids (short chain with 4β8, medium-chain with 6β12, long chain with 16-22 carbon atoms) are activated by fatty acyl-CoA synthases (thiokinases) in the cytosol. The outer mt-membrane enzyme carnitine palmitoyltransferase 1 (CPT-1) generates an acyl-carnitine intermediate for transport into the mt-matrix. Octanoate and palmitate (eight- and 16-carbon saturated fatty acids) may pass the mt-membranes but are frequently supplied to mt-preparations in the activated form of octanoylcarnitine or palmitoylcarnitine.
Electron-transferring flavoprotein complex (CETF) is located on the matrix face of the inner mt-membrane, and supplies electrons from fatty acid Ξ²-oxidation (FAO) to CoQ. FAO cannot proceed without a substrate combination of fatty acids & malate, and inhibition of CI blocks FAO completely. Fatty acids are split stepwise into two carbon fragments forming acetyl-CoA, which enters the TCA cycle by condensation with oxaloacetate (CS reaction). Therefore, FAO implies simultaneous electron transfer into the Q-junction trough CETF and CI.
Abbreviation: FAO
Reference: Gnaiger 2014 MitoPathways
MitoPedia methods:
Respirometry
MitoPedia topics:
Substrate and metabolite
