Hemoglobin-dialdehyde dextran conjugates: Improvement of their oxygen-binding properties with anionic groups

1996 ◽  
Vol 15 (5) ◽  
pp. 461-465 ◽  
Author(s):  
François Bonneaux ◽  
Edith Dellacherie ◽  
Pierre Labrude ◽  
Claude Vigneron
Keyword(s):  
Oxygen Binding ◽  
Binding Properties ◽  
Dialdehyde Dextran ◽  
Anionic Groups

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.

Structural studies of hemoglobin from two flightless birds, ostrich and turkey: insights into their differing oxygen-binding properties

2021 ◽  
Vol 77 (5) ◽  
pp. 690-702
Author(s):  
Pandian Ramesh ◽  
Selvarajan Sigamani Sundaresan ◽  
Nagaraj Shobana ◽  
Thangaraj Vinuchakkaravarthy ◽  
Kandasamy Sivakumar ◽  
...  
Keyword(s):  
Amino Acid ◽  
Structural Features ◽  
Crystal Structure Analysis ◽  
Oxygen Molecule ◽  
Amino Acid Sequences ◽  
Physical Parameters ◽  
Oxygen Binding ◽  
Binding Properties ◽  
Form Analysis ◽  
Inverse Transition

Crystal structures of hemoglobin (Hb) from two flightless birds, ostrich (Struthio camelus) and turkey (Meleagris gallopova), were determined. The ostrich Hb structure was solved to a resolution of 2.22 Å, whereas two forms of turkey Hb were solved to resolutions of 1.66 Å (turkey monoclinic structure; TMS) and 1.39 Å (turkey orthorhombic structure; TOS). Comparison of the amino-acid sequences of ostrich and turkey Hb with those from other avian species revealed no difference in the number of charged residues, but variations were observed in the numbers of hydrophobic and polar residues. Amino-acid-composition-based computation of various physical parameters, in particular their lower inverse transition temperatures and higher average hydrophobicities, indicated that the structures of ostrich and turkey Hb are likely to be highly ordered when compared with other avian Hbs. From the crystal structure analysis, the liganded state of ostrich Hb was confirmed by the presence of an oxygen molecule between the Fe atom and the proximal histidine residue in all four heme regions. In turkey Hb (both TMS and TOS), a water molecule was bound instead of an oxygen molecule in all four heme regions, thus confirming that they assumed the aqua-met form. Analysis of tertiary- and quaternary-structural features led to the conclusion that ostrich oxy Hb and turkey aqua-met Hb adopt the R-/RH-state conformation.

scholarly journals Autoxidation and Oxygen Binding Properties of Recombinant Hemoglobins with Substitutions at the αVal-62 or βVal-67 Position of the Distal Heme Pocket

2013 ◽  
Vol 288 (35) ◽  
pp. 25512-25521 ◽  
Author(s):  
Ming F. Tam ◽  
Natalie W. Rice ◽  
David H. Maillett ◽  
Virgil Simplaceanu ◽  
Nancy T. Ho ◽  
...  
Keyword(s):  
Oxygen Binding ◽  
Binding Properties ◽  
Heme Pocket

Haemoglobin function in aquatic animals: molecular adaptations to environmental challenge

1999 ◽  
Author(s):  
Rufus M. G. Wells
Keyword(s):  
Molecular Mechanisms ◽  
Population Studies ◽  
Selective Advantage ◽  
Oxygen Binding ◽  
Binding Properties ◽  
Diverse Range ◽  
Physiological Adaptations ◽  
Aquatic Vertebrates ◽  
Oxygen Tensions ◽  
Adaptive Nature

The adaptive nature of haemoglobin function in a diverse range of aquatic ectothermic vertebrates is demonstrated by its intrinsic oxygen-binding properties and by erythrocyte cofactor modulation of Hb function. The selective advantage of heterogeneous isohaemoglobins and polymorphic expression of functionally distinct components is considered in relation to environmental oxygen tensions and temperature. The difficulty of comparing physiological adaptations in divergent species is emphasized. Recent population studies suggest that relatively minor differences in environmental conditions, particularly temperature, direct the expression of functionally heterogeneous haemoglobins, although the thresholds for expression have not been established. Regulatory mechanisms underpinning the molecular mechanisms for hypoxic induction of Hb in aquatic vertebrates are not well understood.

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