Biomaterial Database

Structure of deoxyhemoglobin Cowtown [His HC3(146) beta----Leu]: origin of the alkaline Bohr effect and electrostatic interactions in hemoglobin. 1984

M F Perutz, and G Fermi, and T B Shih

Hemoglobin Cowtown [His HC3(146)-beta----Leu] exhibits high oxygen affinity and a halved alkaline Bohr effect. X-ray analysis shows the COOH-terminal leucine to be in equilibrium between two positions: one with the salt bridge between the terminal carboxyl and Lys C5(40)alpha intact and the leucyl side chain leaning against main chain atoms of helices F and FG and the other with the terminal salt bridge broken and the leucyl side chain touching Pro C2(37)alpha. Structural changes are confined to the immediate neighborhood of the COOH terminus, showing the halving of the alkaline Bohr effect to be due directly to the loss of the histidine, without significant contributions from changes in pK values of other ionizable groups due to structural changes elsewhere.

UI	MeSH Term	Description	Entries
D008958	Models, Molecular	Models used experimentally or theoretically to study molecular shape, electronic properties, or interactions; includes analogous molecules, computer-generated graphics, and mechanical structures.	Molecular Models,Model, Molecular,Molecular Model
D011487	Protein Conformation	The characteristic 3-dimensional shape of a protein, including the secondary, supersecondary (motifs), tertiary (domains) and quaternary structure of the peptide chain. PROTEIN STRUCTURE, QUATERNARY describes the conformation assumed by multimeric proteins (aggregates of more than one polypeptide chain).	Conformation, Protein,Conformations, Protein,Protein Conformations
D006455	Hemoglobins, Abnormal	Hemoglobins characterized by structural alterations within the molecule. The alteration can be either absence, addition or substitution of one or more amino acids in the globin part of the molecule at selected positions in the polypeptide chains.	Abnormal Hemoglobins
D006801	Humans	Members of the species Homo sapiens.	Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D006863	Hydrogen-Ion Concentration	The normality of a solution with respect to HYDROGEN ions; H+. It is related to acidity measurements in most cases by pH	pH,Concentration, Hydrogen-Ion,Concentrations, Hydrogen-Ion,Hydrogen Ion Concentration,Hydrogen-Ion Concentrations
D000595	Amino Acid Sequence	The order of amino acids as they occur in a polypeptide chain. This is referred to as the primary structure of proteins. It is of fundamental importance in determining PROTEIN CONFORMATION.	Protein Structure, Primary,Amino Acid Sequences,Sequence, Amino Acid,Sequences, Amino Acid,Primary Protein Structure,Primary Protein Structures,Protein Structures, Primary,Structure, Primary Protein,Structures, Primary Protein
D013329	Structure-Activity Relationship	The relationship between the chemical structure of a compound and its biological or pharmacological activity. Compounds are often classed together because they have structural characteristics in common including shape, size, stereochemical arrangement, and distribution of functional groups.	Relationship, Structure-Activity,Relationships, Structure-Activity,Structure Activity Relationship,Structure-Activity Relationships