2009 Volume 51 Issue 6 Pages 327-333
Gap junctions, which consist of arrays of intercellular channels, permit the exchange of ions and small molecules between adjacent cells. Here, we describe the structural determination of a gap junction channel composed of connexin 26 at 3.5 Å resolution. During each step of the purification process, the protein was examined using electron microscopy and/or dynamic light scattering. Dehydration of the crystals improved the resolution limits. Phase refinement using multi-crystal averaging in conjunction with non-crystallographic symmetry averaging resulted in an electron density map for model building. The amino-acid sequence of a protomer structure was assigned to the electron density map.