Tetrameric coiled coil domain of Sandal virus phosphoprotein

The high resolution X-ray structure of the Sendai virus oligomerization dom ain reveals a homotetrameric coiled coil structure with many details that a re different from classic foiled coils with canonical hydrophobic heptad re peats. Alternatives to the classic knobs-into-holes packing lead to differe nces in supercoil pitch and diameter that allow water molecules inside the core. This open and more hydrophilic structure does not seem to be destabil ized by mutations that would be expected to disrupt classic coiled coils.