In addition to the other suggestions, I would recommend looking at Dr.
Merritt's webpage on anomalous scattering for a clear graphical explanation
of the anomalous difference Fourier map:
http://skuld.bmsc.washington.edu/scatter/AS_Bijvoet.html
On Fri, Aug 29, 2014 at 2:43 PM, Alexander Aleshin
Could anyone remind me how to calculate anomalous difference Fourier maps
using model-calculated phases? I was doing it by
(1) calculating PHcalc from a pdb file using Sfall, then
(2) merging PHcalc with Dano of experimental SFs, then
(3) calculating a map with Dano and PHcalc using FFT
I think the answer is in this paper:
LOW-RESOLUTION ELECTRON-DENSITY AND ANOMALOUS-SCATTERING-DENSITY MAPS OF CHROMATIUM HIGH-POTENTIAL IRON PROTEIN
By: STRAHS, G; KRAUT, J
JOURNAL OF MOLECULAR BIOLOGY Volume: 35 Issue: 3 Pages: 503- Published:
1968
On Fri, 29 Aug 2014, Alexander
See also:
page 141 in The Bijvoet-Difference Fourier Synthesis,
Jeffrey Roach, METHODS IN ENZYMOLOGY, VOL. 374
Pavel
On Fri, Aug 29, 2014 at 12:17 PM, Ronald E Stenkamp
stenk...@u.washington.edu wrote:
I think the answer is in this paper: LOW-RESOLUTION ELECTRON-DENSITY AND
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Here is how I view this stuff. In general the diffraction pattern
does not obey Fridel's law, which means that the actual electron
density map is a set of complex numbers. The map that consists of
just the real part of these density values is
The request to calculate a map using DANO means the CCP4 implemtation of
the FFT program moves the input PHIC phase by 90 degrees as Zbysek says..
Eleanor
On 29 August 2014 20:23, Pavel Afonine pafon...@gmail.com wrote:
See also:
page 141 in The Bijvoet-Difference Fourier Synthesis,
You might consider using AnoDe (J. Appl. Cryst. 44 (2011) 1285-1287).
This program and its documentation are available via the SHELX homepage.
You will need a PDB file name.pdb of the native structure and a file
name_fa.hkl that contains the anomalous differences. You can use SHELXC
or XPREP
The CCP4 FFT program does the 90-degree rotation automatically if you
use DANO= as the column assignment. The rotation is because anomalous
difference arise from scattering that is 90 degrees out of phase with
normal electrons.
-James Holton
MAD Scientist
On 8/29/2014 11:43 AM, Alexander
