Vitreoscilla haemoglobin (VHb) is a type of haemoglobin found in the Gram-negative aerobic bacterium, Vitreoscilla. It is the first haemoglobin discovered from bacteria, but unlike classic haemoglobin it is composed only of a single globin molecule.[1] Like typical haemoglobin, its primary role is binding oxygen, but it also performs other functions including delivery of oxygen to oxygenases, detoxification of nitric oxide, sensing and relaying oxygen concentrations, peroxidase-like activity by eliminating autoxidation-derived H2O2 that prevents haeme degradation and iron release.[2]
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