Hi All, Sorry for a non CCP4 querry. I am using CNS for composite omit map calculations. the structure is having a ligand for which parameter and topology files have been generated using PRODRG server. however while running composite_omit_map.inp i m getting the following torsion topology error (where chain D is the ligand):
"ERROR: There are no suitable base groups. This problem can be caused by isolated bonding networks with undefined or weak dihedral force constants. The atoms that cannot be placed in a tree are listed below: %atoms "D "-242 -AMG -O4 %atoms "D "-242 -AMG -C4 %atoms "D "-242 -AMG -C3 %atoms "D "-242 -AMG -O3 %atoms "D "-242 -AMG -C2 %atoms "D "-242 -AMG -O2 %atoms "D "-242 -AMG -C1 %atoms "D "-242 -AMG -O1 %atoms "D "-242 -AMG -C7 %atoms "D "-242 -AMG -O5 %atoms "D "-242 -AMG -C5 %atoms "D "-242 -AMG -C6 %atoms "D "-242 -AMG -O6 %TORSION:TOPOLOGY error encountered: Fatal Topology Error (CNS is in mode: SET ABORT=NORMal END) ***************************************************** ABORT mode will terminate program execution. ***************************************************** Program will stop immediately." topology and parameter files have been attached to this posting. Kindly suggest if there is any problem with topology or parameter file or i am missing on something else. with best regards Vineet Gaur
mam.param
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mam.top
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