Re: [ccp4bb] non-identical complexes in the asymmetric unit

2010-09-09 Thread Eleanor Dodson
I use PISA to analyse this - sometimes the differences depend on the definition of "what is a hydrogen bond?" and unless you have very high resolution it is risky to say there are significant differences.. But certainly there are examples where the results are very significant indeed - you coul

Re: [ccp4bb] non-identical complexes in the asymmetric unit

2010-09-08 Thread Tim Gruene
Hello Rongjin Guan, when I enter 'dimer ncs' at www.ixquick.com, there are quite a few hits, some of which could be of interest for you. Why do you think this could be a crystallization artefact? Tim On Wed, Sep 08, 2010 at 12:50:43PM -0400, Rongjin Guan wrote: > Dear All, > > I have a structur

Re: [ccp4bb] non-identical complexes in the asymmetric unit

2010-09-08 Thread Roger Rowlett
I don't think this is uncommon at all. For example, we published a structure where 10 chains did not bind ligand at all, and 2 chains did in the ASU (see PDB 3E3I). We have also recently solved a structure where two active sites in the ASU are in different states

[ccp4bb] non-identical complexes in the asymmetric unit

2010-09-08 Thread Rongjin Guan
Dear All, I have a structure with two complexes in the asymmetric unit, and the interactions on the interface are not the same in the two complexes. Briefly, there are two additional hydrogen bonds in one complex, but not in the other. This coule be due to crystallization artefact, but may have