Allosteric mechanisms underlying the adaptive increase in hemoglobin-oxygen affinity of the bar-headed goose.

ABSTRACT: The high blood-O₂ affinity of the bar-headed goose (Anser indicus) is an integral component of the biochemical and physiological adaptations that allow this hypoxia-tolerant species to undertake migratory flights over the Himalayas. The high blood-O₂ affinity of this species was originally attributed to a single amino acid substitution of the major hemoglobin (Hb) isoform, HbA, which was thought to destabilize the low-affinity T state, thereby shifting the T-R allosteric equilibrium towards the high-affinity R state. Surprisingly, this mechanistic hypothesis has never been addressed using native proteins purified from blood. Here, we report a detailed analysis of O₂ equilibria and kinetics of native major HbA and minor HbD isoforms from bar-headed go

SUBMITTER: Jendroszek A 

PROVIDER: S-EPMC6176913 | biostudies-literature | 2018 Sep

REPOSITORIES: biostudies-literature