PMID: 6646231Dec 1, 1983

Absence of cooperative haemoglobin-oxygen binding in Sphenodon, a reptilian relict from the Triassic

R M WellsT Brittain


It is generally accepted that the sigmoidal nature of the haemoglobin-oxygen dissociation curve (ODC) is necessary for efficient oxygen transport in terrestrial vertebrates because it allows large volumes of oxygen to be bound or released for relatively small changes in the partial pressure of oxygen (PO2) in the blood. Furthermore, the amount of oxygen to tissues is increased by hydrogen ions produced from the dissociation of carbon dioxide in solution. The generality of these key features of cooperative oxygen binding and the Bohr effect holds for reptiles, birds and mammals, including representatives with special respiratory requirements for diving, burrowing and living at high altitude. Sphenodon punctatus is the sole surviving representative of the ancient order of 'beakhead' reptiles (order Rhynchocephalia) which were once widely distributed during the Triassic period before the spectacular radiation of dinosaur faunas. We have now investigated the oxygen transporting properties of blood from Sphenodon and find that the ODC is hyperbolic, with a high affinity for oxygen and very small Bohr effect. This combination of characteristics is unique among terrestrial vertebrates and accords with a low demand for oxygen and limit...Continue Reading


Dec 29, 1975·Journal of Molecular Evolution·M L Coates
Sep 29, 1978·Pflügers Archiv : European journal of physiology·M MeyerP Scheid
Dec 1, 1978·Scientific American·M F Perutz
Oct 1, 1976·Analytical Biochemistry·W Jelkmann, C Baufer
Sep 1, 1973·Analytical Biochemistry·R E BeneschS Yung
Apr 1, 1970·British Journal of Haematology·S M LewisJ V Dacie
Jan 1, 1966·Canadian Journal of Physiology and Pharmacology·P V VittorioD Linkletter
Mar 1, 1967·British Journal of Haematology·S M Lewis, J V Dacie
Apr 1, 1982·Respiration Physiology·G N Lapennas, P L Lutz
Apr 1, 1982·Respiration Physiology·P L Lutz, G N Lapennas
Jan 1, 1981·Annual Review of Physiology·G L KooymanR W Davis
Aug 1, 1982·Analytical Biochemistry·G R Bartlett
Jan 1, 1981·Methods in Enzymology·A Riggs
Feb 1, 1980·Respiration Physiology·C P Black, S M Tenney
Oct 1, 1980·The Journal of Experimental Zoology·K JohansenR E Weber

Related Concepts

Plasma Protein Binding Capacity
Hydrogen-Ion Concentration
Allosteric Regulation
Biological Evolution

Trending Feeds


Coronaviruses encompass a large family of viruses that cause the common cold as well as more serious diseases, such as the ongoing outbreak of coronavirus disease 2019 (COVID-19; formally known as 2019-nCoV). Coronaviruses can spread from animals to humans; symptoms include fever, cough, shortness of breath, and breathing difficulties; in more severe cases, infection can lead to death. This feed covers recent research on COVID-19.

Chronic Fatigue Syndrome

Chronic fatigue syndrome is a disease characterized by unexplained disabling fatigue; the pathology of which is incompletely understood. Discover the latest research on chronic fatigue syndrome here.

Synapse Loss as Therapeutic Target in MS

As we age, the number of synapses present in the human brain starts to decline, but in neurodegenerative diseases this occurs at an accelerated rate. In MS, it has been shown that there is a reduction in synaptic density, which presents a potential target for treatment. Here is the latest research on synapse loss as a therapeutic target in MS.

Artificial Intelligence in Cardiac Imaging

Artificial intelligence (ai) techniques are increasingly applied to cardiovascular (cv) medicine in cardiac imaging analysis. Here is the latest research.

Position Effect Variegation

Position Effect Variagation occurs when a gene is inactivated due to its positioning near heterochromatic regions within a chromosome. Discover the latest research on Position Effect Variagation here.

Social Learning

Social learning involves learning new behaviors through observation, imitation and modeling. Follow this feed to stay up to date on the latest research.

Cell Atlas of the Human Eye

Constructing a cell atlas of the human eye will require transcriptomic and histologic analysis over the lifespan. This understanding will aid in the study of development and disease. Find the latest research pertaining to the Cell Atlas of the Human Eye here.

Single Cell Chromatin Profiling

Techniques like ATAC-seq and CUT&Tag have the potential to allow single cell profiling of chromatin accessibility, histones, and TFs. This will provide novel insight into cellular heterogeneity and cell states. Discover the latest research on single cell chromatin profiling here.

Genetic Screens in iPSC-derived Brain Cells

Genetic screening is a critical tool that can be employed to define and understand gene function and interaction. This feed focuses on genetic screens conducted using induced pluripotent stem cell (iPSC)-derived brain cells.