Binding of coumarins to site I of human serum albumin. Effect of the fatty acids.
It is known that binding site I on human serum albumin (HSA) consists of a zone of two overlapping regions: the specific binding region represented by warfarin binding and the specific binding region represented by azapropazone and phenylbutazone binding. In this paper binding parameters to defatted HSA and to HSA with fatty acids (molar ratio of fatty acid/HSA = 4) were compared. High-affinity binding sites for warfarin, 4-chromanol, 4-hydroxycoumarin, coumarin, 3-acetylcoumarin and phenylbutazone (759,549 M-1 > Ka > 67,024 M-1) constitute binding site I on HSA. In this binding area defatted HSA can bind two molecules of warfarin, but the presence of fatty acids diminish the binding capacity of warfarin to HSA (2 > n > 1).
Zatón
A M
AM
Departamento de Bioqumica y Biología Molecular, Facultad de Farmacia,Universidad del Pas Vasco, Vitoria-Gasteiz, Spain.
Ferrer
J M
JM
Ruiz de Gordoa
J C
JC
Marquínez
M A
MA
D001692:Biological Transport / Q000502:physiology; D002839:Chromans / Q000378:metabolism; D003374:Coumarins / Q000378:metabolism*; D005227:Fatty Acids / Q000378:metabolism*; D006801:Humans; D008024:Ligands; D010653:Phenylbutazone / Q000378:metabolism; D017457:Receptors, Albumin / Q000378:metabolism*; D012709:Serum Albumin / Q000378:metabolism*; D014859:Warfarin / Q000378:metabolism
D002839:Chromans; D003374:Coumarins; D005227:Fatty Acids; D008024:Ligands; D017457:Receptors, Albumin; D012709:Serum Albumin; D014859:Warfarin; C029141:2,2,5,7,8-pentamethyl-1-hydroxychroman; D010653:Phenylbutazone