From the statistics you posted, it seems like the integration went quite reasonably. There is a slight undercompleteness in the high resolution bin (82% is a bit on the low end but since this is for phasing I'd expect a traceable map in light of this).
Do the diffraction images indicate very strong (say I/sd > 4) spots beyond 3A? If so then it seems that they're being rejected in the final analysis, possibly due to overlaps. If so, I would certainly recollect this data to obtain the higher resolution spots for refinement (not necessarily for phasing). Depending on how long you've been at this, I'd be eager to solve the structure first :) Go with a synchrotron source, Pt anomalous peak is nearer to 1.1A than 1.54A. Except with the iodide data. Did that have a great anomalous signal? F On Jul 16, 2012, at 8:35 PM, Jason Busby wrote: > Hi, > > This is what I thought when collecting the data - the spots did not look to > be overlapping. I have actually got 4 datasets (native, mercury, iodide and > platinum soaks) and they all index as the same spacegroup and unit cell (the > Pt soak being slightly larger unit cell). This is of a large heterodimer, > and this unit cell would put 2 in the ASU and a solvent content of 56%, so > this seems reasonable. > > Mosflm also picks the same unit cell, and the predictions seem to match up > with spots (although mosflm predicts lots of overlaps) > > Cheers, > > Jason. > > -- > Jason Busby > PhD Student > Laboratory of Structural Biology > School of Biological Sciences > University of Auckland > Thomas Building 110 > 3a Symonds St > Private Bag 92019 > Auckland 1142 > New Zealand > > ph: +64 9 3737599 ext 84155 > fx: +64 9 3737414 > > On 17/07/2012, at 2:53 PM, Francis E Reyes wrote: > >> The cell predictions look like they're overlapping but the spots are not. At >> first glance it looks like the unit cell is incorrect and is too large. >> >> You seem to have intense spots mixed in with weak spots at the same >> resolution. Smells like multiple unit cells / cracked crystal (which if >> close together would confuse the autoindex into thinking it's a larger unit >> cell. . Difficult to tell without seeing the images. >> >> The data/spots (not the predicted spots) show reasonable separation. >> >> >> >> How does the unit cell of the derivative compare with the native? >> >> F >> >> >> >> On Jul 16, 2012, at 2:52 PM, Jason Busby wrote: >> >>> Hi, >>> >>> I have a crystal with a large unit cell in P21221 (a=134 b=151 c=276) and >>> I'm wondering if I have a problem with overlaps. I have a native dataset, >>> and am trying to get phases. I've collected a Pt soak data set on our home >>> source with a 0.5˚ oscillation angle, but the anomalous signal drops off >>> after about 8Å. I am wondering if this is a problem due to overlaps at >>> higher resolution. >>> >>> The Pt dataset has been integrated with XDS, and there don't seem to be too >>> many rejects, but looking at FRAME.CBF it looks like the predicted spots >>> are overlapping at higher resolution. You can see a zoomed-in part of >>> FRAME.CBF here: >>> http://imgur.com/1WShV >>> >>> Should I be concerned with this? The crystal mosaicity from XDS is 0.25, >>> so fairly low. What can I do about this, should I try smaller oscillation >>> angles? >>> >>> Thanks, >>> >>> Jason. >>> >>> -- >>> Jason Busby >>> PhD Student >>> Laboratory of Structural Biology >>> School of Biological Sciences >>> University of Auckland >>> Thomas Building 110 >>> 3a Symonds St >>> Private Bag 92019 >>> Auckland 1142 >>> New Zealand >>> >>> ph: +64 9 3737599 ext 84155 >>> fx: +64 9 3737414 >>> >> >> >> >> --------------------------------------------- >> Francis E. Reyes PhD >> 215 UCB >> University of Colorado at Boulder >> >> >> >> >> >> >
