Re: [ccp4bb] refmac5.7 refine pesudo-translational symmetry

2012-08-01 Thread Qixu Cai
Dear Randy, Thanks very much for your detailed explanation and helpful advice. I have run the phaser job just as you have said. This is the result. The resolution of this dataset is 2.45A. = I added the three commands to phaser

Re: [ccp4bb] refmac5.7 refine pesudo-translational symmetry

2012-08-01 Thread Eleanor Dodson
Are your unit cell and SG correct? I think you maybe should reindex to get a cell volume 25% of this one, and maybe SG P21 That patterson peak is enormous.. Eleanor On 1 Aug 2012, at 08:45, Qixu Cai wrote: > Dear Randy, > > Thanks very much for your detailed explanation and helpful advice. I hav

Re: [ccp4bb] refmac5.7 refine pesudo-translational symmetry

2012-08-01 Thread Qixu Cai
Dear Eleanor, The cell dimensions of the dataset with tNCS are 63.995 75.459 128.860 90.00 90.00 90.00 in P 2 21 21 space group. But for the other dataset without tNCS of the same protein, the cell dimensions are 64.203 65.319 76.443 90.00 90.00 90.00 in C 2 2 21. So the cell volume

[ccp4bb] Reminder (and reduced subscription fees): CNIO Frontiers Meeting on Allosteric Regulation of Cell Signalling, Madrid, 17-19 September 2012

2012-08-01 Thread Daniel Lietha
Dear colleagues, This is to remind you about the upcoming CNIO Frontiers Meeting on Allosteric Regulation of Cell Signalling in Madrid, on 17-19 September 2012. Further, in light of the economic difficulties many scientists are facing, we are offering subscriptions at reduced cost: Students and

[ccp4bb] Process multiple data sets

2012-08-01 Thread Uma Ratu
Dear All: I collected 5 data sets from one crystal and would like to process them together. Here is how I did: In HKL2000, load the all data sets. "Index" each set. When I try "Intergrate", the program automatically go through the whole data sets there, and do not go through. I then process dat

[ccp4bb] Iron induced reduction of crystal

2012-08-01 Thread RHYS GRINTER
Hi All, I'm currently working of a protein with a ferredoxin protein with anIron-Sulphur cluster. I was harvesting some crystals the other day and a piece of my scalpel blade broke off and ended up in the well solution. I Sealed the well without noticing, the shard of iron oxidised and the crys

Re: [ccp4bb] Process multiple data sets

2012-08-01 Thread Uma Ratu
The data sets were collected from the same crystal by "scan" collecting 40 frames from each section. The space group of this crystal is P2. My guess that I may have to index and integrate each set indivadually, and then scale them together. Thanks Uma On Wed, Aug 1, 2012 at 9:01 AM, Machius, Mi

Re: [ccp4bb] Iron induced reduction of crystal

2012-08-01 Thread Peter Moody
Take a look at http://en.wikipedia.org/wiki/Great_Oxygenation_Event This might suggest you may have used up the available oxygen. If you would like to try growing your crystals in an oxygen-free environment, we (in Leicester) have a glove box with a Douglas Instruments Oryx 4 robot. I know its n

Re: [ccp4bb] Process multiple data sets

2012-08-01 Thread Harry Powell
Hi I'd process (i.e. index, refine, integrate) each data set individually, check that (at least) they all have the same crystal system, then combine the datasets using Pointless. Then scale with Aimless. Of course, I'd use Mosflm/Pointless/Aimless rather than HKL, but that's another que

Re: [ccp4bb] Iron induced reduction of crystal

2012-08-01 Thread Herman . Schreuder
Hi, To me this looks like a simple redox displacement reaction which has nothing to do with oxygen. E.g. if one puts a piece of iron in a coppersulfate solution, the more noble copper ions take electrons from the less noble iron and will come out of solution as a metal, while the less noble iron

Re: [ccp4bb] Process multiple data sets

2012-08-01 Thread Phil Evans
Note that neither Aimless nor Scala will do a particularly good job at scaling data from Denzo or Scalepack, since the output files from Scalepack are missing essential geometrical information. They work well with data from Mosflm or XDS (or Saint) (although AFAIK the XDS & Saint scaling program

Re: [ccp4bb] Process multiple data sets

2012-08-01 Thread Uma Ratu
Please correct me if I am wrong: The HKL is not good to combine multiple data sets, even they are come from the same crystal? With HKL, I also tried this way: Index, integrate each data set individually, they all have the same space group. Then scale them together. Still, the graph from scale o

Re: [ccp4bb] Process multiple data sets

2012-08-01 Thread Clemens Vonrhein
Hi Umu, apart from the other suggestions: you could also give autoPROC (www.globalphasing.com and proc-deve...@globalphasing.com) a try - which should deal with such a scenario automatically ... if the image headers are correct ;-) Please let us know, if you want more details off-list ... Cheers

Re: [ccp4bb] Process multiple data sets

2012-08-01 Thread Harry Powell
Hi I don't think Phil or I are saying that HKL is not a good tool to use in this case - but (*) I develop Mosflm, so I have a certain bias. (*) As far as Pointless and Aimless are concerned, to get the best out of them you need to have some geometrical information that the authors of HKL

[ccp4bb] MR with Phaser

2012-08-01 Thread Uma Ratu
Dear All: I try to use Phaser to solve the structure by Molecular Replacement. The data set is collected @180 degree. I process the data using HKL, and have resonable good score: rejection (0.05), Linear R-factor (0.038), completeness (98.3), resolution (50-1.5). I then use Phaser to do MR. The

Re: [ccp4bb] MR with Phaser

2012-08-01 Thread Nat Echols
On Wed, Aug 1, 2012 at 11:27 AM, Uma Ratu wrote: > The protein is in tetramer form. I define this by using the residue number > (1332) which is 4 x monomer. > > After run, Phaser only gave 9 partial solutions, and no solution with all > components. The resulted PDB contains only dimer form of the

[ccp4bb] Enhancing Crystal Quality

2012-08-01 Thread Yi-Liang Liu
Hi CCP4BBers, I have a protein crystallized with 0.2mM Mg acetate and PEG 8000 or 0.1mM cacodylate, pH 6.5, 0.2 Mg acetate, PEG 3350. Both of the conditions gave triangle pyramid like crystals. I brought the crystals to synchrotron using 30% PEG 400 as cryoprotactant, the resolution was only be

Re: [ccp4bb] Enhancing Crystal Quality

2012-08-01 Thread Antony Oliver
Have you tried different cryoprotectants? Can make a huge difference. Also, have you shot an xtal at room temp - to see what the intrinsic diffraction limit is? Additive screens? If all else fails you may well need to explore a different expression construct. Tony. Sent from my iPhone On 1

Re: [ccp4bb] Process multiple data sets

2012-08-01 Thread Uma Ratu
I notice one thing with my data sets. The unit cells is slightly different from each other. For example, one has a/b/c @ 79/126/83. The other has a/b/c @ 84/127/90. Although they are collected from the same crystal. Is this the reason that I can't index both with same parameter in HKL? And subseq

Re: [ccp4bb] Process multiple data sets

2012-08-01 Thread Pete Meyer
Hi Uma, I've used HKL2000 to combine datasets from different crystals, so it's definitely possible to do so (although depending on the data volume it may be better to deal with scalepack directly). There are two things that you don't mention about your data - the (approximate) resolution, an

Re: [ccp4bb] Process multiple data sets

2012-08-01 Thread Edwin Pozharski
> The unit cells is slightly different from each other. For example, one has > a/b/c @ 79/126/83. The other has a/b/c @ 84/127/90. Although they are > collected from the same crystal. This is very substantial difference and with unit cell expanding by ~20% one would expect scaling problems.  Try

Re: [ccp4bb] Enhancing Crystal Quality

2012-08-01 Thread Roger Rowlett
You might be killing crystals with the cryosolvent. Try soaking the crystals briefly in well solution + 25-30% glucose or sucrose prior to flash cooling. You can also try other cryoprotectants: glycerol, EG, etc. You can also try sequential brief soaks in gradually increasing cryoprotectant concent

Re: [ccp4bb] Enhancing Crystal Quality

2012-08-01 Thread Yi-Liang Liu
Hi, Thanks for the kindly answers from everyone. I actually haven't tried different cryoprotectants. I might will give a try next time. I usually only use mother liquor+30% PEG400. It is noticeable that it has some "patterns (cracks (?))" on the crystal. However, it didn't form icy rings or etc