Binding of p-cresylsulfate and p-cresol to human serum albumin studied by microcalorimetry.
p-Cresylsulfate, a metabolite of p-cresol, is reported as prototypic protein-bound uremic toxin, inefficiently removed by haemodialysis. The binding between p-cresylsulfate or p-cresol and human serum albumin was studied using microcalorimetry. The results confirm that the two molecules are protein-bound. However, the affinity of p-cresylsulfate and p-cresol toward human serum albumin is moderate at 25 degrees C and becomes relatively weak at physiological temperature, 37 degrees C. The binding principally involves van der Waals type interactions, and the binding sites of the two molecules are the same or very close. The low fraction of bound toxin (13-20%) appears to be insufficient to link strong binding to poor removal of this toxin by hemodialysis.
Bergé-Lefranc
David
D
Laboratoire de Chimie Générale, Prévention des Risques et Nuisances Technologiques, EA 1784 Biogénotoxicité et Mutagenèse Environnementale FR3098 ECCOREV, Université de la Méditerranée, Faculté de Pharmacie, 13005 Marseille, France.
Chaspoul
Florence
F
Calaf
Raymond
R
Charpiot
Philippe
P
Brunet
Philippe
P
Gallice
Philippe
P
D001665:Binding Sites; D002151:Calorimetry; D003408:Cresols / Q000737:chemistry* / Q000378:metabolism; D006801:Humans; D011485:Protein Binding; D006435:Renal Dialysis; D012709:Serum Albumin / Q000737:chemistry* / Q000378:metabolism; D013463:Sulfuric Acid Esters; D013696:Temperature; D013816:Thermodynamics
D003408:Cresols; D012709:Serum Albumin; D013463:Sulfuric Acid Esters; C032538:4-cresol; C408690:4-cresol sulfate