Biochemical and functional characterization of Rapana thomasiana hemocyanin.

1. The hemocyanin (Hc) of the marine gastropod mollusc Rapana thomasiana was collected from animals living on the west coast of the Black Sea and characterized for its biochemical and functional properties. 2. This Hc is very similar to other gastropod Hcs as far as amino acid composition, general structure and reactivity of the binuclear copper active site are concerned. 3. Some peculiarities in the dissociation-reassociation pattern are observed in comparison to other gastropod Hcs, in particular with respect to the ability to form sopramolecular aggregates. 4. Changes in pH disclose a strong reverse Bohr effect. Different R and T states are required to describe the oxygen binding curves at the different pHs.