pH and haemoglobin oxygen affinity in blood from the Antarctic cod Dissostichus mawsoni

1977 ◽  
Vol 67 (1) ◽  
pp. 77-88
Author(s):  
J. Qvist ◽  
R. E. Weber ◽  
A. L. DeVries ◽  
W. M. Zapol
Keyword(s):  
Molecular Mechanisms ◽  
Oxygen Affinity ◽  
Oxygen Binding ◽  
Low Oxygen ◽  
Binding Properties ◽  
Dissostichus Mawsoni ◽  
Blood Ph ◽  
The Antarctic ◽  
Low Oxygen Affinity

Blood pH in the antarctic cod (Dissostichus mawsoni) and in two Trematomus species, occlrring at --1-9 degrees C, is extremely high (approximately 8-2 to 8-3). This supports and extends Rahn's (1966) model for the temperature-pH relationship in cold-blooded vertebrates. The blood of D. mawsoni shows a low oxygen affinity (P50 approximately equal to 14-5 mmHg at pH 8–16 and −1-9 degrees C). Despite normal in vitro temperature and pH sensitivities, blood P50 increases only slightly when live fish are temperature-stressed (+ 4-0 degrees C), or become acidotic as a result of agitational stress (blood pH 7–71), primarily as a result of compensatory decreases in blood ATP levels. Oxygen-binding properties of ‘stripped’ (cofactor-free) solutions of D. mawsoni haemoglobin were measured in attempts to elucidate the molecular mechanisms involved in the function of the pigment.

Regulation of Blood Oxygen Affinity in the Australian Blackfish Gadopsis Marmoratus: I. Correlations between Oxygen-binding Properties, Habitat and Swimming Behaviour

1982 ◽  
Vol 99 (1) ◽  
pp. 223-243
Author(s):  
G. P. DOBSON ◽  
J. BALDWIN
Keyword(s):  
Whole Blood ◽  
Oxygen Affinity ◽  
Swimming Behaviour ◽  
Oxygen Binding ◽  
Blood Oxygen ◽  
Low Oxygen ◽  
Binding Properties ◽  
Molar Ratios ◽  
Blood Oxygen Affinity ◽  
Low Oxygen Affinity

1. The regulation of whole blood oxygen affinity in the freshwater blackfish Gadopsis marmoratus Richardson has been examined, and correlations made between oxygen-binding properties and the habitat and swimming behaviour of the fish. 2. Blackfish whole blood has a low oxygen affinity relative to other fish bloods reported in the literature. This is not due to a low oxygen affinity of the stripped haemoglobins, but arises from interactions between haemoglobin and intraerythrocytic modulators. 3. The presence of high concentrations of ATP, and to a lesser extent GTP, in the erythrocyte, together with the effect of these nucleoside triphosphates on the oxygen affinity of haemoglobin solutions at physiological NTP: Hb4 molar ratios, demonstrates that this class of compounds is a major regulator of oxygen affinity in blackfish blood. 4. The oxygen affinities of whole blood and haemoglobin solutions are sensitive to pH, with haemoglobin solutions displaying a relatively large alkaline Bohr coefficient of - 1.05 over the physiologically relevant pH range of 6.5–7.0. 5. Although increasing Pco2, lowers the oxygen affinity of whole blood, it does so only through the effect on pH, as pH-buffered haemoglobin solutions show no oxygen-linked CO2 binding. This lack of oxygen-linked CO2 binding has not been reported for any other naturally occurring vertebrate haemoglobins. 6. Muscle morphology and biochemistry, and behavioural observations, indicate that the blackfish uses anaerobic energy metabolism during rapid swimming and in recovery. 7. It is concluded that the oxygen-binding properties of blackfish blood reflect adaptations for maintaining adequate tissue oxygenation for animals at rest and during slow sustained swimming in waters of high oxygen tensions.

scholarly journals Haemoglobin polymorphisms affect the oxygen-binding properties in Atlantic cod populations

2008 ◽  
Vol 276 (1658) ◽  
pp. 833-841 ◽  
Author(s):  
Øivind Andersen ◽  
Ola Frang Wetten ◽  
Maria Cristina De Rosa ◽  
Carl Andre ◽  
Cristiana Carelli Alinovi ◽  
...  
Keyword(s):  
Evolutionary Biology ◽  
Quaternary Structure ◽  
Atlantic Cod ◽  
Three Dimensional ◽  
Oxygen Affinity ◽  
Oxygen Binding ◽  
Low Oxygen ◽  
Binding Properties ◽  
Important Species ◽  
The North

A major challenge in evolutionary biology is to identify the genes underlying adaptation. The oxygen-transporting haemoglobins directly link external conditions with metabolic needs and therefore represent a unique system for studying environmental effects on molecular evolution. We have discovered two haemoglobin polymorphisms in Atlantic cod populations inhabiting varying temperature and oxygen regimes in the North Atlantic. Three-dimensional modelling of the tetrameric haemoglobin structure demonstrated that the two amino acid replacements Met55β 1 Val and Lys62β 1 Ala are located at crucial positions of the α 1 β 1 subunit interface and haem pocket, respectively. The replacements are proposed to affect the oxygen-binding properties by modifying the haemoglobin quaternary structure and electrostatic feature. Intriguingly, the same molecular mechanism for facilitating oxygen binding is found in avian species adapted to high altitudes, illustrating convergent evolution in water- and air-breathing vertebrates to reduction in environmental oxygen availability. Cod populations inhabiting the cold Arctic waters and the low-oxygen Baltic Sea seem well adapted to these conditions by possessing the high oxygen affinity Val55–Ala62 haplotype, while the temperature-insensitive Met55–Lys62 haplotype predominates in the southern populations. The distinct distributions of the functionally different haemoglobin variants indicate that the present biogeography of this ecologically and economically important species might be seriously affected by global warming.

Oxygen binding by single red blood cells from the red-eared turtle Trachemys scripta

2001 ◽  
Vol 90 (5) ◽  
pp. 1679-1684 ◽  
Author(s):  
Sebastian Frische ◽  
Stefano Bruno ◽  
Angela Fago ◽  
Roy E. Weber ◽  
Andrea Mozzarelli
Keyword(s):  
Red Blood Cells ◽  
Blood Cells ◽  
Oxygen Affinity ◽  
Trachemys Scripta ◽  
Oxygen Binding ◽  
Binding Properties ◽  
Cell Variation ◽  
Insight Into

Oxygen-binding properties of single red blood cells from the red-eared turtle Trachemys scripta were measured by microspectrophotometry to describe the variation in oxygen affinity of red blood cells and to gain insight into the distribution of functionally different hemoglobins among red blood cells. Methodologically, this study represents the first report on the cell-to-cell variation in oxygen-binding properties based on oxygen-binding curves of single vertebrate red blood cells. The cells differed significantly with respect to oxygen affinity. Mean oxygen pressure at half saturation of the cells in a blood sample was found to be 20.1 ± 3.3 (SD) Torr. The distribution of oxygen affinities among red blood cells is unimodal, indicating that the two hemoglobins found in turtle blood are not segregated in distinct cells. Therefore, the functional interaction shown by these hemoglobins in vitro is likely to take place in vivo. The considerable variation in oxygen affinity between individual red blood cells calls for its incorporation in models of tissue oxygenation.

scholarly journals Structure of liganded T-state haemoglobin from cat (Felis silvestris catus), a low oxygen-affinity species, in two different crystal forms

2014 ◽  
Vol 70 (7) ◽  
pp. 1898-1906 ◽  
Author(s):  
Moovarkumudalvan Balasubramanian ◽  
Ponnuraj Sathya Moorthy ◽  
Kamariah Neelagandan ◽  
Ramya Ramadoss ◽  
Prasanna R. Kolatkar ◽  
...  
Keyword(s):  
Mammalian Species ◽  
Oxygen Affinity ◽  
Structural Features ◽  
Low Oxygen ◽  
Felis Silvestris Catus ◽  
Binding Properties ◽  
Crystal Forms ◽  
Allosteric Effectors ◽  
T State ◽  
Low Oxygen Affinity

Haemoglobin (Hb) is an iron-containing metalloprotein which plays a major role in the transportation of oxygen from the lungs to tissues and of carbon dioxide back to the lungs. Hb is in equilibrium between low-affinity tense (T) and high-affinity relaxed (R) states associated with its unliganded and liganded forms, respectively. Mammalian species can be classified into two groups on the basis of whether they express `high' or `low' oxygen-affinity Hbs. Although Hbs from the former group have been studied extensively, a more limited number of structural studies have been performed for low oxygen-affinity Hbs. Here, the crystal structure of low oxygen-affinity cat methaemoglobin (metHb) has been solved at 2.0 and 2.4 Å resolution in two different crystal forms. Even though both structures are fully liganded, they unusually adopt a T-state-like quaternary conformation but with several localized R-like tertiary-structural and quaternary-structural features. The study provides atomic-level insights into the ligand-binding properties of this Hb, including its low cooperativity, blunt response to allosteric effectors and low affinity for oxygen, as well as further contributing to the mechanism underlying Hb allostery.

scholarly journals Rat embryonic and foetal erythrocytes. High 2,3-bisphosphoglycerate and ATP and low oxygen affinity in vitro for nucleated embryonic cells

1980 ◽  
Vol 192 (1) ◽  
pp. 355-359 ◽  
Author(s):  
J G Gilman
Keyword(s):  
Oxygen Affinity ◽  
High Oxygen ◽  
Red Cells ◽  
Embryonic Cells ◽  
Low Oxygen ◽  
Foetal Life ◽  
High Oxygen Affinity ◽  
Low Oxygen Affinity

Embryonic nucleated red cells of the rat have high ATP and 2,3-bisphosphoglycerate and relatively low oxygen affinity. During foetal life they are replaced by large non-nucleated red cells with high ATP, low bisphosphoglycerate and high oxygen affinity. After birth, small non-nucleated red cells with high bisphosphoglycerate and low oxygen affinity rapidly predominate.

HB Washtenaw [βT11(A8)VAL-PHE]: An Electrophoretically Silent, Unstable, Low Oxygen Affinity Variant Associated with Anemia and Chronic Cyanosis

Hemoglobin ◽  
1994 ◽  
Vol 18 (4-5) ◽  
pp. 285-295 ◽  
Author(s):  
K. Krishnan ◽  
F. Martinez ◽  
R. T. Wille ◽  
R. T. Jones ◽  
D. T. Shin ◽  
...  
Keyword(s):  
Oxygen Affinity ◽  
Low Oxygen ◽  
Low Oxygen Affinity

Purification, Crystallization and Preliminary X-Ray Diffraction Studies on Goat (Capra hircus) Hemoglobin - A Low Oxygen Affinity Species

2009 ◽  
Vol 16 (4) ◽  
pp. 454-456 ◽  
Author(s):  
Ponnuraj Moorthy ◽  
Kamariah Neelagandan ◽  
Moovarkumudalvan Balasubramanian ◽  
Mondikalipudur Ponnuswamy
Keyword(s):  
Oxygen Affinity ◽  
Capra Hircus ◽  
Low Oxygen ◽  
X Ray Diffraction ◽  
X Ray ◽  
Hemoglobin A ◽  
Low Oxygen Affinity

Influence of carbon monoxide on hemoglobin-oxygen binding

1976 ◽  
Vol 41 (6) ◽  
pp. 893-899 ◽  
Author(s):  
M. P. Hlastala ◽  
H. P. McKenna ◽  
R. L. Franada ◽  
J. C. Detter
Keyword(s):  
Carbon Monoxide ◽  
Oxygen Affinity ◽  
Co2 Concentration ◽  
Bohr Effect ◽  
Oxygen Binding ◽  
Dissociation Curve ◽  
Low Oxygen ◽  
Oxygen Dissociation ◽  
Initial Binding ◽  
Fixed Acid

The oxygen dissociation curve and Bohr effect were measured in normal whole blood as a function of carboxyhemoglobin concentration [HbCO]. pH was changed by varying CO2 concentration (CO2 Bohr effect) or by addition of isotonic NaOH or HCl at constant PCO2 (fixed acid Bohr effect). As [HbCO] varied through the range of 2, 25, 50, and 75%, P50 was 26.3, 18.0, 11.6, and 6.5 mmHg, respectively. CO2 Bohr effect was highest at low oxygen saturations. This effect did not change as [HbCO] was increased. However, as [HbCO] was increased from 2 to 75%, the fixed acid Bohr factor increased in magnitude from -0.20 to -0.80 at very low oxygen saturations. The effect of molecular CO2 binding (carbamino) on oxygen affinity was eliminated at high [HbCO]. These results are consistent with the initial binding of O2 or CO to thealpha-chain of hemoglobin. The results also suggest that heme-heme interaction is different for oxygen than for carbon monoxide.

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