title: Probable binding region of small hydrophobic molecules on hemoglobin. Spin label-induced nuclear magnetic relaxation.
abstract: The interactions of phenylalanine, valine and alanine with hemoglobin have been compared using spin lattice nuclear magnetic relaxation and spin label-enhanced nuclear magnetic relaxation measurements. The results indicate that phenylalanine exhibits weak hydrophobic binding to hemoglobin, and that the binding site is probably located within about 7-13 A of the nitroxide free electron of spin-labeled hemoglobin. This distance is consistent with the binding site being located within a hydrophobic region comprised of the side chains of the beta-chain residues, phenylalanine beta 85, leucine beta 88 and leucine beta 91, and perhaps a segment of the beta heme porphyrin ring.
mesh_terms: D000409:Alanine / Q000378:metabolism*; D001665:Binding Sites; D003497:Cyclic N-Oxides; D006441:Hemoglobin A / Q000378:metabolism*; D006451:Hemoglobin, Sickle / Q000378:metabolism*; D006801:Humans; D009682:Magnetic Resonance Spectroscopy; D010649:Phenylalanine / Q000378:metabolism*; D011485:Protein Binding; D013113:Spin Labels; D014633:Valine / Q000378:metabolism*
chemical_list: D003497:Cyclic N-Oxides; D006451:Hemoglobin, Sickle; D013113:Spin Labels; C017480:4-maleimido-2,2,6,6-tetramethylpiperidinooxyl; D010649:Phenylalanine; D006441:Hemoglobin A; D014633:Valine; D000409:Alanine