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Biomedical subjects

Q H Gibson

Publications and source records attributed to Q H Gibson.

At least 127 records · Page 7Linked to original sources
PubMed1973

The contribution of the alpha and beta chains to the kinetics of oxygen binding to and dissociation from hemoglobin.

A new type of experiment in which hemoglobin is exposed briefly to oxygen has shown that the half-time of dissociation of oxygen from some partly oxygenated intermediates is about 1 msec at 20 degrees and 10 msec at 2 degrees . The rapid dissociation occurs selectively from one type of chain, provisionally identified as the beta-chain. Chains that show the rapid rate of dissociation of oxygen also bind rapidly. It follows that the kinetic equivalent of the Adair equation and the Monod-Wyman-Changeux model are quite unsuited to represent the kinetics of the oxygen-hemoglobin reaction. The reaction of oxygen with hemoglobin closely resembles that of the alkyl isocyanides and differs radically from that of carbon monoxide.

Hemoglobins↗
PubMed1973

Oxygen equilibrium and kinetics of isolated subunits from hemoglobin Kansas.

The isolated beta subunit of hemoglobin Kansas has an oxygen affinity that is as low relative to the oxygen affinity of the beta(A) subunit as the affinity of hemoglobin Kansas is low relative to hemoglobin A. Thus the low affinity properties of hemoglobin Kansas are almost completely reflected in the properties of the isolated subunits. The kinetic results show that the equilibrium affinity difference results both from a much larger oxygen dissocation rate constant in beta(Kansas) (k = 37 sec(-1) and 18 sec(-1) for beta(Kansas) and beta(A), respectively) and from a lower association reaction rate, The properties of the alpha chains from hemoglobins A and Kansas appear to be identical, as expected.

Carboxyhemoglobin↗