A structural model for the interaction of haem with unsaturated fatty acids explaining its quasi-lipoxygenase activity. Quantum chemical calculations.
The quasi-lipoxygenase activity of haemoglobin differs in many respects from the well-known haemin-catalyzed lipid peroxidation (1-4), especially in its high substrate specificity for unsaturated fatty acids containing one 1,4-pentadiene system (dienoic fatty acids). In this report a structural model for the fatty acid haem interaction based on quantum-chemical calculations is presented which show that only dienoic fatty acids are bound to the haem in such a way that the initial hydrogen abstraction that is necessary for the over-all reaction, is favoured sterically and energetically.
D000818:Animals; D002417:Cattle; D055598:Chemical Phenomena; D002621:Chemistry; D005231:Fatty Acids, Unsaturated; D006418:Heme; D006454:Hemoglobins / Q000378:metabolism; D008084:Lipoxygenase / Q000378:metabolism*; D008958:Models, Molecular
D005231:Fatty Acids, Unsaturated; D006454:Hemoglobins; D006418:Heme; D008084:Lipoxygenase