Proline puckering. Prolines with funny puckers: Date= 2011-05-23 14:34:37 Puckering amplitudes for all PRO residues are within normal ranges. The proline residues listed in the table below have a puckering phase that is not expected to occur in protein structures. Puckering parameters were calculated by the method of Cremer and Pople [REF]. Normal PRO rings approximately show a so-called envelope conformation with the C-gamma atom above the plane of the ring (phi=+72 degrees), or a half-chair conformation with C-gamma below and C-beta above the plane of the ring (phi=-90 degrees). If phi deviates strongly from these values, this is indicative of a very strange conformation for a PRO residue, and definitely requires a manual check of the data. Be aware that this is a warning with a low confidence level. See: Who checks the checkers? Four validation tools applied to eight atomic resolution structures [REF]. 103 PRO ( 103 ) A 104.8 envelop C-beta (108 degrees) ------------------------------------------------------------------------ If you have detected any error, or have any question or suggestion, please send an Email to Gert Vriend. Roland Krause, Jens Erik Nielsen, Gert Vriend . ------------------------------------------------------------------------ Last modified Mon May 23 14:34:41 2011