Hello Niu,
1. We need extra information. What program did you use ? What's the
similarity (e.g. % identity) of your model. What's your space group ?
Did you try ALL the space groups in your point group in ALL the
permutations (e.g. in primitive orthorhombic there are 8 possibilities).
1a. My best guess on limited info is that you've got a partial solution
in the wrong space group with only part of the molecules at their
correct position.
2. I recently had a very unusual case where I could solve a structure
in EITHER P41212 or P43212 with similar statistics, but that I would see
interpenetrating electron density for a second, partial occupancy
molecule no matter which of these space groups I tried (and it showed
this when I expanded the data to P1). Might conceivably be a 2:1
enantiomorphic twin, in retrospect, but we obtained a more friendly
crystal form. I hope you don't have something like that, but it's possible.
Phil Jeffrey
Princeton
On 11/14/13 5:22 PM, Niu Tou wrote:
> Dear All,
>
> I have a strange MR case which do not know how to interpret, I wonder if
> any one had similar experiences.
>
> The output model does not fit into the map at all, as shown in picture
> 1, however the map still looks good in part regions. From picture 2 we
> can see even clear alpha helix. I guess this could not be due to some
> random density, and I have tried to do MR with a irrelevant model
> without producing such kind of regular secondary structure.
>
> This data has a long c axis, and in most parts the density are still not
> interpretable. I do not know if this is a good starting point. Could any
> one give some suggestions? Many thanks!
>
> Best,
> Niu
>
>
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