CoA-independent transfer of arachidonic acid from 1,2-diacyl-sn-glycero-3-phosphocholine to 1-O-alkyl-sn-glycero-3-phosphocholine (lyso platelet-activating factor) by macrophage microsomes.
Macrophage microsomes catalyzed the transfer of arachidonic acid (20:4) from 1,2-diacyl-glycerophosphocholine (GPC) to 1-alkyl-GPC (lyso platelet-activating factor). This enzyme reaction did not require the presence of cofactors such as Co A. Free arachidonic acid or linoleic acid-labeled phospholipids failed to act as the acyl donor. These results suggest that the reaction is a CoA-independent direct transfer of arachidonic acid. This arachidonoyl transacylation system may play a very important role in the metabolism of lyso platelet-activating factor and also in the elimination or release of arachidonic acid from diacyl-GPC.
D000255:Adenosine Triphosphate / Q000378:metabolism; D000818:Animals; D016718:Arachidonic Acid; D001095:Arachidonic Acids / Q000378:metabolism*; D019826:Cholic Acid; D002793:Cholic Acids / Q000494:pharmacology; D003065:Coenzyme A / Q000378:metabolism*; D008264:Macrophages / Q000378:metabolism*; D008274:Magnesium / Q000378:metabolism; D008861:Microsomes / Q000378:metabolism; D010713:Phosphatidylcholines / Q000378:metabolism*; D010972:Platelet Activating Factor / Q000031:analogs & derivatives* / Q000096:biosynthesis / Q000378:metabolism; D011796:Quinacrine / Q000494:pharmacology; D011817:Rabbits
D001095:Arachidonic Acids; D002793:Cholic Acids; C029271:O-deacetyl platelet activating factor; D010713:Phosphatidylcholines; D010972:Platelet Activating Factor; D016718:Arachidonic Acid; D000255:Adenosine Triphosphate; D019826:Cholic Acid; D011796:Quinacrine; D008274:Magnesium; D003065:Coenzyme A