On 05/06/14 16:10, George Devaniranjan wrote:
Hi,
First off I am pretty new to CCP4/X-ray crystallography so please bear
with me as I try to explain my question.
I was looking at a protein structure from the PDB (let's say 1aho.pdb).
I have the corresponding MTZ file. I wanted to calculate the R-factor
for some selected residues (lets say 17-40).
I can calculate the R factor for the whole protein using the (MTZ +
pdb file) SFCheck tool.
Is there a way to calculate the R-factor for a segment of the protein?
I can generate a masked map using COOT as follows:
Extensions--> Maps--> Mask Map by Atom Selection (inverse)
But the result is a map and not a MTZ file
(the format I need for the next step SFCheck)
I tried using NCSMask but it did not work out.
Could someone suggest where I am going wrong in trying to calculate R
for a small part of the protein?
Try something like this:
mapmask MAPIN coot-out-masked.map MAPOUT tmp.map << !
AXIS Z X Y
END
!
sfall MAPIN tmp.map HKLOUT sfs-from-map.mtz << !
MODE SFCALC MAPIN
SYMM 1
!
You might not need the mapmask step.
Paul.
