Binding of Photobilirubin to Human Serum Albumin.

Autor: Lamola, Angelo A, Flores, Jorge, Blumberg, William E.
Předmět:
Zdroj: European Journal of Biochemistry; 4/15/83, Vol. 132 Issue 1, p165-169, 5p
Abstrakt: Results of experiments based upon circular dichroic spectra suggest that configurationaily (Z → E) isomerized bilirubin (photobilirubin) binds to human serum albumin at the primary bilirubin binding site with an affinity only 2 - 3-times lower than that of bilirubin. The high affinity of photobilirubin for albumin, comparable to that of bilirubin, supports the roles of albumin in the stabilization and transport of the isomerized pigment in viva and strongly suggests that albumin also functions to sequester photobilirubin effectively, reducing its toxic potential. The high affinity of photobilirubin for albumin predicts that the isomerized pigment, formed in large amounts during phototherapy for neonatal hyperbilirubinemia, should not appear in the fast-diazo-reacting (`direct') bilirubin pool nor should it interfere with nonspectroscopic bilirubin binding tests. These predictions were confirmed for the Evelyn and Malloy diazo assay for `direct' bilirubin and a Sephadex chromatography method for assessing `loosely bound' plasma bilirubin. [ABSTRACT FROM AUTHOR]
Databáze: Complementary Index