Do you expect more than one molecule in the asymmetric unit? Determined from the Matthews Coefficient (poor), size exclusion column (better), or self RF (best) ?
On Nov 7, 2013, at 8:36 AM, Zhihong Yu <nkyuz...@gmail.com> wrote: > Hi, all > > I'm a rookie in resolving a brand new structure. I have some questions for my > current case and look forward to some suggestions. > > Now I’m working on a protein like this: > N-ter(55aa)—domainA(110aa)—linker(30aa)—domainB(150aa)—C-ter(20aa), I got a > diffraction data just to 3.5Å, and there is no complete homology structure in > pdb bank, but only a homology structure (named as structureX later) for > domainB with ~30% sequence identity, so I have some questions as following: > > 1. Is it possible to find a resolution through MR approach using structureX > as a search model? Especially considering that the resolution is only 3.5Å. > Currently I just tried once using phaser and refine the structure, I can get > a R/Rfree of 0.45/0.55, and it looks like most of backbone in the structureX, > especially those within helix or sheet, can be well described by 2Fo-Fc > density. Is this primary result promising or not? > > 2. If it’s possible, what’s the general optimal procedure I should follow? > > Really thanks for any advice and suggestions! > > Zhihong > --------------------------------------------- Francis E. Reyes PhD 215 UCB University of Colorado at Boulder
