Self rotations can be helpful, but often are not! or worse stull are
misleading.. It isnt worth spending a lot of time puzzling over them.
Once you have solvedthe structure they become amazingly easy to interpret!
When you import intensity data to mtz, either via scala or other
processing programs, you will have a message saying whether there is any
non-cryst translation. If there is the molecules related bu the
translation will be in the same relative orientation to the crystal axes
and the self-rotation between them will be overlapped by the origin or a
crystallographic symmetry operator.
Other problems - the molecules are randomly orientated relative to each
other and since molrep only illustrates 2-folds 3-folds etc, you have no
picture. However if you look at the peak list you may find something
significantly above background.
The molecules have different structures.
It may help to do the self rotation ate relatively low resolution
good luck Eleanor
Peter Grey wrote:
Dear Marie,
Look for peaks at your native Patterson map which might indicate
pseudo-translation NCS that can not be detected by self-rotation.
Peter.
On Fri, Jul 16, 2010 at 10:04 PM, Marie Lacroix <
lacroix.ma...@rocketmail.com> wrote:
Hi everybody,
I just calculated a self rotation function from the data used for molecular
replacement (what by the way did not worked) and saw no peak at all. Does
this not mean that there is only one molecule in the AU and no additional
crystallographic axis? Matthews suggested 3-7 molecules. Sorry for this
basic question, but I still have some problems with these self rotation
functions, even when I see not one peak...
Marie
