Figure 2: 3D reconstructed structure of the Euglena IP39 crystal.
From: The four-transmembrane protein IP39 of Euglena forms strands by a trimeric unit repeat
(a) 3D map of the IP39 crystal lattice viewed parallel to the two-fold axis from the luminal side of vesicular membrane. The grey mesh represents the EM density map contoured at 1.3σ. The internal molecular surfaces coloured blue and red represent two distinct pseudo-symmetric strands of the densities contoured at 3σ. The black box and closed ovals indicate a unit cell and two-fold symmetry axes, respectively. The right-angled arrows indicate the directions of the a- and b-axes. The black bar represents 50 Å. (b) Three-dimensional map viewed parallel to the membrane plane. Colour representations of the EM density map are the same as in a. The light grey bands represent the location of the lipid bilayer with a thickness of 35 Å. The asterisks indicate the pseudo two-fold axes along the b-axis. The numbers beside the double-headed arrows indicate the dimensions of a unit cell.
