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Thanks to all for the helpful comments! I will try all and let you know if any work. I found the Borgstahl papers mentioned, and I will try out the methods in those papers as well. On Mon, Apr 18, 2016 at 11:57 AM, Edward Snell <[log in to unmask]> wrote: > Hi Jarrod, > > > > My guess would be that you may have two things going on in the crystal. > The first is modulation. A PubMed search on Gloria Borgstahl should pull up > some nice papers in this area. The satellite peaks around the main > reflection (and fractional Miller indices) are a signature for this. > Overlaid on this is that you have either a cracked or multiple crystal in > the loop. Picking reflections manually and just taking the centroids of > each ‘cross’ might change the indexing but I’d take a close look at the > predictions and actual reflections to see if the satellites are being > accounted for in the space group you are using. It may be challenging to > get good structural information from this data. > > > > Cheers, > > > > Eddie > > > > Edward Snell Ph.D. > > CEO Hauptman-Woodward Medical Research Institute > > Assistant Prof. Department of Structural Biology, University at Buffalo > > 700 Ellicott Street, Buffalo, NY 14203-1102 > > Phone: (716) 898 8631 Fax: (716) 898 8660 > > Skype: eddie.snell Email: [log in to unmask] > > > > Heisenberg was probably here! > > > > Gordon Research Conference on Diffraction Methods in Structural Biology, > July 17th-22nd 2016. Save the date. > > > > *From:* CCP4 bulletin board [mailto:[log in to unmask]] *On Behalf Of *Jarrod > Mousa > *Sent:* Monday, April 18, 2016 11:18 AM > *To:* [log in to unmask] > *Subject:* [ccp4bb] Unusual diffraction > > > > Dear community, > > > > I collected data from a crystal grown in 30% PEG 8000, 200 mM ammonium > sulfate, 100 mM sodium cacodylate pH 6.4 and 40% v/v Pentaerythritol > ethoxylate (3/4 EO/OH), and cryoprotected with 20% glycerol. I am attaching > a snapshot of the diffraction pattern along with a zoomed in portion. I am > having trouble solving by molecular replacement, even though I have a very > good starting model. Just wanted to get people's insights into the odd (at > least to me) diffraction pattern. The data can process with XDS in P 4 2 2. > I also attached merging statistics. > > > > Thank you, > > > > Jarrod Mousa > > Post-doctoral research fellow > > Crowe Laboratory > > Vanderbilt University Medical Center > > >