On Fri, 30 Nov 2012 17:27:41 -0500, Sarathy Karunan Partha <sarathyus...@gmail.com> wrote:
>Dear all, > >Here is the XSCALE.LP output after scaling for the izit dye stained >crystak. Sorry for attaching the .INP file. > >Sarathy > >On Fri, Nov 30, 2012 at 4:19 PM, Sarathy Karunan Partha < >sarathyus...@gmail.com> wrote: > >> Dear all, >> >> >> >> We did some Izit dye staining to test our crystal (salt or protein) and we >> observed that the crystal didn�t take up the dye well. But, showed nice >> protein diffraction (home source KCr 2.2909 A) and we collected a dataset >> (360 frames, 1o osc, 5 min exposure) on this dye stained crystal. The >> data collection statistics looks great and most interestingly we saw some >> anomalous signal for this data (see attached XSCALE.LP). Hi Sarathy, it would be worth investigating which systematic error prevents your data from having a higher ISa - 10 is really low. Have you tried re-running INTEGRATE CORRECT after "mv GXPARM.XDS XPARM.XDS" ? Based on the Chi^2 values, you might want to try STRICT_ABSORPTION_CORRECTION=TRUE . If that significantly (say more than 10%) increases ISa and also improves the other statistics, then I would go for it. best, Kay >> >> >> >> This protein was crystallized in 0.2 M Ca acetate, 30 % PEG 400 pH 4.5. >> Izit dye is basically methylene blue which contains a sulfur atom >> (phenothiazine ring) and also has some basic dimethylamio groups. Our >> protein has many acidic residues that could enhance binding of this basic >> dye.We think the anomalous signal could be from this dye and the heavy atom >> search with autoSHARP and Phenix autosol is suggestive of 4 sulfur atoms. >> >> >> Did anyone come across similar situation with using this dye and also >> welcome any suggestions about using this data for S-SAD phasing. >> >> >> Thanks, >> Sarathy >> >
