Direct Phasing of Coiled-Coil Protein Crystals

Coiled-coil proteins consisting of multiple copies helices take part in transmembrane transportation and oligomerization, are used for drug delivery. Cross-alpha amyloid-like coiled-coil structures, which tens short align perpendicular to the fibril axis, often resist molecular replacement due uncertainty position each helix. Eight structures already solved posted protein data bank reconstructed ab initio demonstrate direct phasing results. Non-crystallographic symmetry intermediate-resolution diffraction considered phasing. The retrieved phases have a mean phase error around 30∼40°. calculated density map is ready model building, agrees with deposited structure. results indicate that an efficient approach construct envelope from scratch, build helix without bias also confirm prediction AlphaFold RosettaFold, solve whole structure proteins.