Thermodynamics of oxygen binding to arctic hemoglobins. The case of reindeer.
Détails
ID Serval
serval:BIB_62721C598FCB
Type
Article: article d'un périodique ou d'un magazine.
Collection
Publications
Institution
Titre
Thermodynamics of oxygen binding to arctic hemoglobins. The case of reindeer.
Périodique
Biophysical Chemistry
ISSN
0301-4622 (Print)
ISSN-L
0301-4622
Statut éditorial
Publié
Date de publication
1990
Peer-reviewed
Oui
Volume
37
Numéro
1-3
Pages
281-286
Langue
anglais
Résumé
The most surprising characteristic of reindeer hemoglobin (Hb) concerns its response to changes in temperature. Thus, the shape of the oxygen-binding curve is strongly temperature dependent due to the difference in the enthalpy of oxygenation between the T and R state of the molecule. In fact, delta H of oxygen binding to the T state is strongly exothermic whereas that of the R state is very close to zero or possibly positive after correction for the heat of oxygen solubilization. Moreover, the allosteric transition T0----R0 has been found to display a negative delta H and a contemporaneous decrease in entropy, a behavior which is precisely the opposite of what has been reported for other hemoglobins. As a whole, reindeer Hb represents a beautiful example of the significance that comparative studies may have in assessing the general validity of the main properties of the hemoglobin molecule.
Mots-clé
2,3-Diphosphoglycerate, Animals, Arctic Regions, Diphosphoglyceric Acids/metabolism, Hemoglobin A/metabolism, Hemoglobins/metabolism, Humans, Hydrogen-Ion Concentration, Kinetics, Mathematics, Models, Theoretical, Oxyhemoglobins/metabolism, Protein Conformation, Reindeer/blood, Thermodynamics
Pubmed
Web of science
Création de la notice
03/08/2014 14:35
Dernière modification de la notice
20/08/2019 15:19