TY - JOUR
T1 - Serum albumin binding of palmitate and stearate. Multiple binding theory for insoluble ligands
AU - Brodersen, Rolf
AU - Vorum, Henrik
AU - Skriver, Elisabeth
AU - Pedersen, Anders Overgaard
PY - 1989/6/1
Y1 - 1989/6/1
N2 - In usual studies of ligand binding to a carrier, free and bound ligand concentrations are measured in equilibrium mixtures with varying carrier and ligand concentrations. The observed data are then analyzed by a binding equation such as Scatchard's or the general binding equation. With palmitic, stearic and oleic acids as ligands we found that the aqueous solubility is too low to allow this procedure. We have consequently transformed the general binding equation so that it does not contain parameters related to aqueous solutions of the ligand. While the classical binding equations describe affinities of transfer of a ligand from an aqueous solution to the carrier, the new equation is valid for transfer of a ligand from one bound state to another, i.e. for relative binding description. The relative binding constants, L1, L2, L3 ... Li, in the new equation thus define the transfer affinity for the ligand from a 1:1 complex with a standard carrier to an i:1 complex of the ligand with the carrier investigated. Binding of palmitate and stearate to human serum albumin was studied by determination of dialytic exchange rates between identical fatty acid/albumin solutions. The results were analyzed by the new equation without reference to ligands in aqueous solution.
AB - In usual studies of ligand binding to a carrier, free and bound ligand concentrations are measured in equilibrium mixtures with varying carrier and ligand concentrations. The observed data are then analyzed by a binding equation such as Scatchard's or the general binding equation. With palmitic, stearic and oleic acids as ligands we found that the aqueous solubility is too low to allow this procedure. We have consequently transformed the general binding equation so that it does not contain parameters related to aqueous solutions of the ligand. While the classical binding equations describe affinities of transfer of a ligand from an aqueous solution to the carrier, the new equation is valid for transfer of a ligand from one bound state to another, i.e. for relative binding description. The relative binding constants, L1, L2, L3 ... Li, in the new equation thus define the transfer affinity for the ligand from a 1:1 complex with a standard carrier to an i:1 complex of the ligand with the carrier investigated. Binding of palmitate and stearate to human serum albumin was studied by determination of dialytic exchange rates between identical fatty acid/albumin solutions. The results were analyzed by the new equation without reference to ligands in aqueous solution.
KW - Chlorides/metabolism
KW - Dialysis
KW - Fatty Acids/analysis
KW - Humans
KW - Kinetics
KW - Mathematics
KW - Models, Theoretical
KW - Palmitates/analysis
KW - Palmitic Acids/analysis
KW - Protein Binding
KW - Scattering, Radiation
KW - Serum Albumin/metabolism
KW - Solubility
KW - Stearates/analysis
KW - Stearic Acids/analysis
U2 - 10.1111/j.1432-1033.1989.tb14795.x
DO - 10.1111/j.1432-1033.1989.tb14795.x
M3 - Journal article
C2 - 2731550
SN - 0014-2956
VL - 182
SP - 19
EP - 25
JO - European Journal of Biochemistry
JF - European Journal of Biochemistry
IS - 1
ER -