Accession Number : AD0670748

Title :   STUDIES OF HEME-PROTEINS.

Descriptive Note : Final rept. 21 Aug 64-31 Oct 66,

Corporate Author : MINNESOTA UNIV MINNEAPOLIS LAB FOR BIOPHYSICAL CHEMISTRY

Personal Author(s) : Lumry,Rufus

Report Date : 1966

Pagination or Media Count : 9

Abstract : Techniques were developed for preparing homogeneous hemoglobin free of contaminants and detailed studies were conducted on association and dissociation of the hemoglobin tetramer as a function of salt concentration. Binding of oxygen and carbon monoxide ligands to hemoglobin as indirectly observed by spectrophotometric techniques lack agreement with predictions based on the Adair mechanism. A theoretical basis for this discrepancy was developed in this laboratory and preliminary experimental data utilizing direct gasometric measurements show that a method is now available to directly measure heme-heme interaction and that much of the present literature on the subject may be incorrectly interpreted. The binding of xenon to myoglobin was examined in detail. At least two xenon binding sites interact cooperatively with the binding of carbon monoxide and a small molecule contaminant links this ligand-ligand interaction. Thermodynamic studies on myoglobin implicate important conformational changes during ligand binding. (Author)

Descriptors :   (*HEMOGLOBIN, MOLECULAR ASSOCIATION), BLOOD PROTEINS, SPECTROPHOTOMETERS, MEASUREMENT, XENON, CARBON MONOXIDE, OXYGEN, SODIUM CHLORIDE, BLOOD CHEMISTRY, DISSOCIATION, RECOMBINATION REACTIONS, CHROMATOGRAPHIC ANALYSIS, CHROMOPROTEINS, CHEMICAL EQUILIBRIUM, PURIFICATION

Subject Categories : Biochemistry

Distribution Statement : APPROVED FOR PUBLIC RELEASE