title: A spectroscopic study of the hemin-human-alpha-fetoprotein system.
abstract: The binding of hemin to human alpha-fetoprotein has been estimated by means of fluorescence and spectrophotometric titration. Spectrophotometric titration discloses one strong binding site for hemin with an association constant of 1.5 X 10(7) M-1. The binding causes a shift of the absorption maximum to a higher wavelength and a rise in the molar absorption coefficient. Fluorescence reveals that the binding of hemin to human AFP quenches the protein fluorescence, which changes in character from a tryptophan type to a tyrosine type. As postulated by our results, the binding of hemin to human AFP is similar to the binding of hemin to HSA.
mesh_terms: D005260:Female; D005470:Fluorometry; D006418:Heme / Q000031:analogs & derivatives*; D006427:Hemin / Q000378:metabolism*; D006801:Humans; D011247:Pregnancy; D012709:Serum Albumin / Q000378:metabolism*; D013053:Spectrophotometry; D000509:alpha-Fetoproteins / Q000378:metabolism*
chemical_list: D012709:Serum Albumin; D000509:alpha-Fetoproteins; D006418:Heme; D006427:Hemin