Crocodiles help to develop artificial blood

A new genetic brew of human and Nile crocodile blood could improve existing artificial blood products in transmitting oxygen to the tissue, says an article in last week's Nature. The new haemoglobin molecule, Hb Scuba, was engineered by researchers at the Medical Research Council's Laboratory of Molecular Biology in Cambridge.

Hb Scuba uses unique elements of the crocodile haemoglobin cell which allow the crocodile to stay underwater on one breath of air for up to an hour. Mammals that dive, such as whales and dolphins, store the extra oxygen they need in their muscle myoglobin and have quite regular haemoglobin, but the crocodile's haemoglobin has evolved to bond with a waste product of respiration, bicarbonate ions, to help the unloading …