The PDB coordinates of the KcsA channel (PDB:1R3J) present the chains in an order that is not conducive to detecting their symmetric arrangement because there is no single transformation that can match all subunits. To address this issue, the chains can be re-arranged starting from a chain at one end of the complex and progressively adding the closest unordered neighbor. Repeating this until all chains have been accounted for allows for the C4 quaternary symmetry to be detected.
