Biomaterial Database

The effect of 2,3-diphosphoglycerate on the solubility of deoxyhemoglobin S. 1986

W N Poillon, and B C Kim, and E V Welty, and J A Walder

Although highly charged polyanions, such as inositol hexaphosphate, have been clearly shown to decrease the solubility of deoxyhemoglobin S, the effect of 2,3-diphosphoglycerate (DPG), the endogenous allosteric effector within the red cell, has been more controversial. In this work we have compared the effect of DPG on the solubility of native deoxyhemoglobin S and a derivative in which the DPG binding site is blocked by cross-linking the two beta 82 lysine residues. At pH 6.6 and 30 degrees C the solubility of deoxyhemoglobin S was found to be decreased by 15% (i.e., from 18.8 to 16.0 g/dl) in the presence of saturating concentrations of DPG. Under the same conditions DPG had no effect on the solubility of the cross-linked derivative. This result establishes unequivocally that the binding of DPG within the beta cleft directly facilitates the polymerization of deoxyhemoglobin S. Under physiological conditions, the solubility of deoxyhemoglobin S was found to be decreased by 6% in the presence of an equimolar concentration of DPG. A solubility decrease of this magnitude is sufficient to enhance the tendency of SS cells to sickle and may exacerbate the clinical symptoms of sickle cell disease.

UI	MeSH Term	Description	Entries
D011485	Protein Binding	The process in which substances, either endogenous or exogenous, bind to proteins, peptides, enzymes, protein precursors, or allied compounds. Specific protein-binding measures are often used as assays in diagnostic assessments.	Plasma Protein Binding Capacity,Binding, Protein
D004163	Diphosphoglyceric Acids	Glyceric acids where two of the hydroxyl groups have been replaced by phosphates.	Bisphosphoglycerates,Acids, Diphosphoglyceric
D006451	Hemoglobin, Sickle	An abnormal hemoglobin resulting from the substitution of valine for glutamic acid at position 6 of the beta chain of the globin moiety. The heterozygous state results in sickle cell trait, the homozygous in sickle cell anemia.	Hemoglobin S,Deoxygenated Sickle Hemoglobin,Deoxyhemoglobin S,Hemoglobin SS,Hemoglobin, Deoxygenated Sickle,SS, Hemoglobin,Sickle Hemoglobin,Sickle Hemoglobin, Deoxygenated
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D000755	Anemia, Sickle Cell	A disease characterized by chronic hemolytic anemia, episodic painful crises, and pathologic involvement of many organs. It is the clinical expression of homozygosity for hemoglobin S.	Hemoglobin S Disease,HbS Disease,Sickle Cell Anemia,Sickle Cell Disease,Sickle Cell Disorders,Sickling Disorder Due to Hemoglobin S,Anemias, Sickle Cell,Cell Disease, Sickle,Cell Diseases, Sickle,Cell Disorder, Sickle,Cell Disorders, Sickle,Disease, Hemoglobin S,Hemoglobin S Diseases,Sickle Cell Anemias,Sickle Cell Diseases,Sickle Cell Disorder
D001665	Binding Sites	The parts of a macromolecule that directly participate in its specific combination with another molecule.	Combining Site,Binding Site,Combining Sites,Site, Binding,Site, Combining,Sites, Binding,Sites, Combining
D012995	Solubility	The ability of a substance to be dissolved, i.e. to form a solution with another substance. (From McGraw-Hill Dictionary of Scientific and Technical Terms, 6th ed)	Solubilities
D019794	2,3-Diphosphoglycerate	A highly anionic organic phosphate which is present in human red blood cells at about the same molar ratio as hemoglobin. It binds to deoxyhemoglobin but not the oxygenated form, therefore diminishing the oxygen affinity of hemoglobin. This is essential in enabling hemoglobin to unload oxygen in tissue capillaries. It is also an intermediate in the conversion of 3-phosphoglycerate to 2-phosphoglycerate by phosphoglycerate mutase (EC 5.4.2.1). (From Stryer Biochemistry, 4th ed, p160; Enzyme Nomenclature, 1992, p508)	2,3-Bisphosphoglycerate,2,3-DPG,2,3-Diphosphoglyceric Acid,2,3-Diphosphoglycerate, (D)-Isomer,Glycerate 2,3-Bisphosphate,2,3 Bisphosphoglycerate,2,3 Diphosphoglycerate,2,3 Diphosphoglyceric Acid,2,3-Bisphosphate, Glycerate