Functional SAXS study of haemocyanin dioxygen-carrier protein

Abstract The effects of conformational rearrangements on dioxygen binding to molluscan haemocyanins have been investigated by small-angle X-ray scattering (SAXS). The SAXS patterns of the oxygenated and deoxygenated forms of Octopus vulgaris haemocyanin are significantly different; whereas the patterns of the two forms of Rapana thomasiana haemocyanin are almost superimposable. A program has been developed, based on the differences in molecular dimensions, in order to simulate the effects observed in the investigation.