A Periodic Table of Coiled-Coil Protein Structures

Coiled coils are protein structure domains with two or more alpha-hetices packed together via interlacing of side chains known as knob-into-hole packing. We analysed and classified a large set of coiled-coil structures using a combination of automated and manual methods. This led to a systematic classification that we termed a periodic table of coiled coils, which we have made available at http://coiledcoils.chm.bris.ac.uk/ccplus/search/periodic-table. In this table, coiled-coil assemblies are arranged in columns with increasing numbers of alpha-helices and in rows of increased complexity. The table provides a framework for understanding possibilities in and limits on coiled-coil structures and a basis for future prediction, engineering and design studies. (C) 2008 Elsevier Ltd. All rights reserved.