17 Beta-estradiol interaction with haptoglobin and its complex with hemoglobin
Isaeva, G.M.; Smirnov, A.N.; Rozen, V.B.; Beĭsembaeva
Biokhimiia 55(9): 1713-1716
1990
ISSN/ISBN: 0320-9725 PMID: 2078644 Document Number: 350154
The estradiol-binding capacity of sheep haptoglobin and its complex with hemoglobin was investigated. It was shown that in the presence of H2O2 the haptoglobin-hemoglobin complex tightly binds 17 beta-estradiol. No dissociation of the estradiol-protein complex occurs after its precipitation with trichloroacetic acid and steroid extraction with the ester. It is supposed that the 17 beta-estradiol is bound to the protein by covalent bonds; this binding is characteristic only of the haptoglobin-hemoglobin complex but not of haptoglobin alone.