High affinity of alpha-foetoprotein for arachidonate and other fatty acids.
Fatty acid analysis of purified bovine alpha-foetoprotein showed it to contain 2.7 mol of fatty acid/mol of alpha-foetoprotein. Purified alpha-foetoprotein focused at isoelectric point 4.8. Removal of bound ligands from alpha-foetoprotein by charcoal treatment changed its isoelectric point to 5.2. This change could be reversed by addition of exogenous fatty acids to the defatted alpha-foetoprotein. Albumin isolated from the same foetal calf serum source as alpha-foetoprotein contained 1.4 mol of fatty acid/mol of protein. alpha-Foetoprotein and albumin contained comparable amounts of fatty acids with 14 to 18 carbon atoms, but alpha-foetoprotein contained 16 times as much of the long-chain polyunsaturated fatty acids as albumin. alpha-Foetoprotein was found to have slightly higher affinity for palmitate and linoleate and severalfold higher affinity for arachidonate than albumin. These findings suggest that alpha-foetoprotein may play a role in the foetal metabolism of the long-chain polyunsaturated fatty acids.
D000818:Animals; D001095:Arachidonic Acids; D002417:Cattle; D005227:Fatty Acids / Q000032:analysis; D007525:Isoelectric Focusing; D007526:Isoelectric Point; D007700:Kinetics; D011485:Protein Binding; D012710:Serum Albumin, Bovine; D000509:alpha-Fetoproteins / Q000302:isolation & purification
D001095:Arachidonic Acids; D005227:Fatty Acids; D000509:alpha-Fetoproteins; D012710:Serum Albumin, Bovine