Question

Scientists recently reconstructed the genome of the wooly mammoth. Mammoth hemoglobin was found to bind oxygen at much lower temperatures than human hemoglobin. using what you've learned, provide an explanation for why the mammoth hemoglobin molecule can operate at much lower temperatures.

Provide molecular mechanism and draw a Hb-O2 dissociation curve for mammoth hemoglobin (superimpose the normal human Hb-O2 curve for comparison).

Answer 1

The mammoth haemoglobin was seen to bind to oxygen at a wide range if temperature specifically at low temperatures. A normal human haemoglobin , the Oxygen binding protein releases oxygen with a slight increase in temperature which shifts the curve to the right. The mammals that lived in cold regions could bind to the oxygen at low temperatures due to the cofactor binding ability. More the cofactors bind to the haemoglobin side chains, less will be the effect of temperature on the oxygen binding affinity. The more chloride ion binding also greatly affects the binding of the gas to the Hb molecules.  Non-synonymous mutations are kind of mutations that were found in the mammoth hemoglobin that allowed the mammals to travel to hgher altitude and easily bind to oxygen at lower temperatures.