I would do a rigid body refinement, rebuild the structure and then go on with refinement. To compare refined structures, you still need to superimpose them first.

Best,

Herman

Von: CCP4 bulletin board [mailto:[log in to unmask]] Im Auftrag von Faisal Tarique
Gesendet: Donnerstag, 24. April 2014 14:01
An: [log in to unmask]
Betreff: [ccp4bb] rigid body refinement or molecular replacement.

Dear all

I have a high resolution (2A) native structure of a protein and structure factors for a relatively low resolution (2.6A) of the same protein bound with its substrate (complex) having same space group and cell parameters (P212121 is the space group and cell parameters are a,b,c =39.4,64.5,117.2. and a,b,c = 39.6,63.9,117.8 for native and complex)..My question is ..what is the best way to solve the complex structure ??..whether it should be done through molecular replacement with the native structure or simply by doing rigid body refinement through mtz from complex and coordinates of the native structures..in summary...what should be the ideal method employed for the structure solution if the aim is to compare between the native and complex structure of the same protein ??.

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Regards

Faisal
School of Life Sciences
JNU