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Protein, All Atom Refinement

Goose Lysozyme

CELL 38.3 65.7 45.2 90 116 90
INCLUDE /usr/local/tnt/data/symmetry/p21b.dat

FO glnatob.hkl
RESOLUTION 1.6

INCLUDE gans.seq

EXCLUDE   3:OD1   3:C
EXCLUDE  97:OD1  97:C
EXCLUDE 108:OD1 108:C
EXCLUDE 168:OD2 168:C
EXCLUDE 182:CG  182:O

CONSTANT OCC

WEIGHT RFACTOR  0.0090
WEIGHT BOND     0.8  ANGLE 1.3  TORSION 0
WEIGHT TRIGONAL 2    PLANE 5    CONTACT 10  BCORREL 0

Goose Lysozyme crystals diffract quite well. The control file shown here varies both the positions and temperature factors of each atom. The occupancies are held fixed because even with 1.6Å resolution data these parameters are not well defined. You will almost never vary occupancy parameters.

Because of the presence of the high resolution data it was decided not to impose the B correlation restraint. The weight of the BCORREL term was set to zero.

The criteria TNT uses to identify a bad contacts seems to be too restrictive in the case of certain atoms in aspartic and glutamic acids. The EXCLUDE cards in the example were placed there because these ``bad'' contacts were determined by the experimenter to be, in fact, proper.



Dale Edwin Tronrud
Wed Jul 5 13:21:03 PDT 2000