Hemocyanin, conformation

Molluscan hemocyanins. Two FUs from moUuscan hemocyanins were resolved, the oxy-form of O. dofleini He FU g (Figure 5b) and the deoxy-form of R. thomasiana He (Figure 5c ). Each FU consists of two domains. The N-terminal domain II carries the active site with a four alpha-helix bundle folding motif with two copper atoms. The C-terminal domain III replaces topologically the domain I in arthropod subunits and looks like a squeezed beta-barrel. Although the Rapana structure is not resolved as well as the Octopus FU, two different conformations can be deduced. In the oxy FU of Octopus hemocyanin, domain III covers the entrance to the active site completely while in the deoxy-form this domain is shifted a few degrees so that the channel to the active site becomes completely uncovered. 

Synthesis and conformational analysis of xylose-containing elements of mollusc hemocyanin glycans... 

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