Publications by authors named "A Bardgard"
Polar bear (Ursus maritimus) hemoglobin (Hb) shows a low response to 2,3-diphosphoglycerate (2,3-DPG), compared to human Hb A0, even though these proteins have the same 2,3-DPG-binding site. In addition, polar bear Hb shows a high response to chloride and an alkaline Bohr effect (deltalog P50/deltapH) that is significantly greater than that of human Hb A0. The difference in sequence Pro (Hb A0)-->Gly (polar bear Hb) at position A2 in the A helix seems to be critical for reduced binding of 2,3-DPG.
View Article and Find Full Text PDFFunctional characterisation of Eskimo dog hemoglobin: II. The interplay of HCO(3)- and Cl-.
Comp Biochem Physiol A Physiol
July 1997
Hemoglobin (Hb) from the Eskimo dog (belonging to Canis lupus familiaris) showed similar Bohr effect (delta log P50/delta pH) to human HbA in the presence of 100 mmol l-1 NaCl at 20 degrees C. The presence of 7% carbon dioxide in the desalted condition caused a positive (reversed) Bohr effect in the pH range 7.1-7.
View Article and Find Full Text PDFArticle Synopsis
- The study examines the oxygen binding properties of hemoglobin in Eskimo dogs in Greenland, noting key hematological parameters like levels of 2,3-DPG and hemoglobin.
- The analysis shows that these dogs have a high oxygen affinity at lower temperatures but this affinity decreases with the presence of chloride ions and 2,3-DPG.
- Findings suggest that the interaction of these compounds may help the dogs efficiently unload oxygen in cooler and more acidic conditions, similar to adaptations seen in arctic ruminants.
Oxygen binding and aggregation of hemoglobin from the common European frog, Rana temporaria.
Comp Biochem Physiol B Biochem Mol Biol
June 1997
The hemoglobin from the European frog, Rana temporaria, consists of one major and three minor components. The tetramers aggregate upon deoxygenation notably at pH 7:3. Aggregation due to formation of disulphide bridges, as occurs in related species, was observed only in polyacrylamide gels.
View Article and Find Full Text PDFThe functional properties of haemoglobin from the Lesser Rorqual whale (Balaenoptera acutorostrata) have been characterized as a function of the heterotropic effector concentrations and temperature. The results obtained suggest the existence of sophisticated modulation mechanisms based on the interplay of organic phosphates, carbon dioxide, lactate and temperature. These, together with the very small apparent heat of oxygenation (delta H) of oxygen binding, have been physiologically interpreted on the basis of the specific metabolic needs of this diving mammal.
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