Temperature acclimation and oxygen-binding properties of blood and multiple haemoglobins of rainbow trout

1976 ◽  
Vol 65 (2) ◽  
pp. 333-345 ◽  
Author(s):  
R. E. Weber ◽  
S. C. Wood ◽  
J. P. Lomholt

Acclimation of rainbow trout to 5, 15 and 22 degrees C for periods exceeding 4 months had no significant effect on the oxygen affinity of whole blood or on the concentration of ATP, which is the main organic phosphate in red cells. Slight differences were, however, found in the oxygenation properties of the haemolysates, which correlate with changes in the relative concentration of the multiple haemoglobins. The oxygen-binding properties of the main haemoglobin components account for the observed differences in the haemolysates. The possible thermoacclimatory significance of changes in haemoglobin multiplicity and co-factor concentrations is discussed.

1982 ◽  
Vol 99 (1) ◽  
pp. 223-243
Author(s):  
G. P. DOBSON ◽  
J. BALDWIN

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.


2008 ◽  
Vol 276 (1658) ◽  
pp. 833-841 ◽  
Author(s):  
Øivind Andersen ◽  
Ola Frang Wetten ◽  
Maria Cristina De Rosa ◽  
Carl Andre ◽  
Cristiana Carelli Alinovi ◽  
...  

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.


1993 ◽  
Vol 175 (1) ◽  
pp. 15-32 ◽  
Author(s):  
G. C. Grigg ◽  
R. M. G. Wells ◽  
L. A. Beard

The P50 of whole blood [30°C, PCO2=2.08 kPa (15.6 mmHg)] decreases during embryonic development from approximately 6.7 kPa (50 mmHg) at 15 days to about half this value at hatching (86 days), paralleling a decrease in ATP from 100 to 5–10 micromole g-1 Hb. There is also a progressive changeover from embryonic to adult haemoglobin (HbA). A pulse of 2,3- diphosphoglycerate (2,3-DPG) (18 micromole g-1 Hb) occurs late in embryonic life. It has no effect on whole-blood oxygen-affinity and falls rapidly at hatching to values typical of post-hatchling crocodilians in general (<1.0 micromole g-1 Hb). ATP has a marked effect on the oxygen affinity of embryonic haemoglobin (HbE) but not on HbA. 2,3-DPG has only very small effects on the oxygen affinities of HbE and HbA. CO2 has a small effect on the oxygen affinity of HbE but a marked effect on that of HbA. Values of PO2 measured in the chorio-allantoic artery [2.9 kPa (22 mmHg)] and vein [5.9 kPa (52 mmHg)] imply an increase in saturation from approximately 30 % to more than 80 %. Neither whole-blood oxygen-affinity nor ATP level was altered in response to an experimental 7-day exposure to low ambient oxygen levels [10.7 kPa (80 mmHg)]. The results do not lend themselves easily to the pan-selectionist paradigm in which all physiological traits are viewed as being adaptive.


Blood ◽  
1997 ◽  
Vol 90 (8) ◽  
pp. 2916-2920 ◽  
Author(s):  
Kazuhiko Adachi ◽  
Patrick Konitzer ◽  
Jian Pang ◽  
Konda S. Reddy ◽  
Saul Surrey

Abstract To clarify the role of γN-terminal Gly, γ5 Glu, and γ143 Ser in 2, 3-biphosphosphoglycerate (BPG) binding to fetal hemoglobin (Hb F ), we engineered and produced normal human Hb F and two Hb F variants (Hb F γG1V, γS143H, and Hb F γG1V, γE5P, γS143H) using a yeast expression system and then compared their oxygen-binding properties with those of native human Hb F and adult Hb (Hb A). Oxygen affinity of Hb F γG1V, γS143H in the absence of 2, 3-BPG was slightly higher than that of normal Hb F. The decrease in oxygen affinities for Hb F γG1V, γS143H with increasing 2, 3-BPG concentrations was larger than that of normal Hb F, but significantly less than that of Hb A. In contrast, oxygen affinities of Hb F γG1V, γE5P, γS143H in the absence and presence of 2, 3-BPG were much lower than those of Hb F γG1V, γS143H and were similar to those of Hb A. These results indicate that differences between Pro and Glu at the A2 position in the A helix in Hb A and Hb F, respectively, are critical for reduced binding of 2, 3-BPG to Hb F, even though β5 Pro does not interact directly with 2, 3-BPG in Hb A. Hb F variants such as Hb F γG1V, γE5P, γS143H, which exhibit reduced oxygen affinity, should facilitate design of efficient antisickling fetal Hb variants for potential use in gene therapy for sickle cell disease.


1978 ◽  
Vol 56 (4) ◽  
pp. 887-890 ◽  
Author(s):  
R. E. Isaacks ◽  
H. D. Kim ◽  
D. R. Harkness

The relationship between whole blood oxygen affinity and erythrocyte (RBC) organic phosphate composition of three species of air-breathing teleosts (Lepidosiren paradoxa, Electrophorus electrocus, and Synbranchus marmoratus) and three pairs of closely related air-breathing and water-breathing fishes (Arapaima gigas vs. Osteoglossum bicirrhosom, Hoplerythrinus unitaeniatus vs. Hoplias malabaricos, and Pterygoplichthys sp. vs. Pseudoplatystoma sp.) have been studied.Packed cell volumes, hemoglobin concentrations, whole blood P50's, and total erythrocyte phosphates are higher in air breathers than in water breathers.GTP and ATP are the predominant organic phosphates in the erythrocytes of all of the species studied except A. gigas, which contains inositol pentaphosphate as the major organic phosphate at a level of 1.8 μmol/cm3 RBC or 39% of the total cell phosphate.


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