title: Binding of meso-tetra(4-sulfonatophenyl)porphine to haemopexin and albumin studied by spectroscopy methods.
abstract: 1. The interaction of haemopexin and albumin with TPPS4 was studied by measuring the absorption and fluorescence spectra. Haemopexin was found to have one strong TPPS4 binding center (Ka = 3 x 10(7) M-1). 2. Haem-haemopexin complex appears to have no specific binding site for TPPS4. Occupation of the specific binding center of haemopexin molecule by a haem abolishes TPPS4 binding. 3. Albumin was found to possess one strong TPPS4 binding center (Ka = 3 x 10(6) M-1) besides two or three weak binding sites (Ka = 2 x 10(5) M-1). 4. Haem-albumin complex possesses only one weak TPPS4 binding site (Ka = 7 x 10(5) M-1). These observations suggest identity of primary binding sites of TPPS4 and haem on albumin molecule.
authors.affiliation: Department of Cell Biochemistry, Institute of Haematology and Blood Transfusion, Praha, Czech Republic.
authors.forename: J
authors.initials: J
authors.lastname: Bartosová
authors.forename: I
authors.initials: I
authors.lastname: Kalousek
authors.forename: Z
authors.initials: Z
authors.lastname: Hrkal
mesh_terms: D001665:Binding Sites; D006466:Hemopexin / Q000378:metabolism*; D006801:Humans; D017319:Photosensitizing Agents / Q000378:metabolism*; D011166:Porphyrins / Q000378:metabolism*; D012709:Serum Albumin / Q000378:metabolism*; D013050:Spectrometry, Fluorescence; D013053:Spectrophotometry
chemical_list: D017319:Photosensitizing Agents; D011166:Porphyrins; D012709:Serum Albumin; C016136:tetraphenylporphine sulfonate; D006466:Hemopexin