That difference density looks too good to be true..
There is obviously a very strong non-crystallographic translation.
Is the spacegroup and/or cell correct?
Eleanor
On Mar 11 2012, xiaoyazi2008 wrote:
Hi All,
I have an interesting thing to share. 2.3A dataset with good quality, P21
Partial model is available (~60% of the target protein). It seems that
there are 4 copies in the ASU (Matthews_coef 2.6, 53%solvent) Molecular
replacement gave two copies of the model (Z scores are R6.2, T6.2, R6.8,
T13.4). The solution is very clear. It could not locate the rest two
copies.
However, a quick refmac5 refinement gave a very high R factor. The funny
part is the symmetry operation in Coot. As shown in the JPEG figure, it
looks like there should be another two copies (based on strong fo-fc
green map), which locate in the empty space between models found by
Phaser.
Why is that Phaser could not find the remaining two copies even there are
strong fo-fc density? Any suggestions...
Thanks a lot!
Zhihong
--
Professor Eleanor Dodson
YSNL, Dept of Chemistry
University of York
Heslington YO10 5YW
tel: 00 44 1904 328259
Fax: 00 44 1904 328266
