Re: [ccp4bb] Problem with Rfree and Rfac

2009-05-26 Thread Eleanor Dodson
The R factor and Rfree will always diverge during refinement; the model is being modified to fit the working set, and not theFree set.. A largish difference at such a resolution is not surprising really. Your rebuilding has improved the FreeR but it isnt surprising thatit has not fallen

Re: [ccp4bb] Re :Re: [ccp4bb] MAD phasing

2009-05-26 Thread Eleanor Dodson
You need to try both P61 22 and P6522 with the Se sites changed fron x,y,z to -x,-y,-z. The anom differences can be explained by either solution. But maybe these programs automatically check both hands? Eleanor Dodson Ethayathulla Abdulsamath wrote: hi BertThank you for your reply. Your are

Re: [ccp4bb] Experimental design and response surface methods for crystal optimization

2009-05-26 Thread Patrick Shaw Stewart
Hi Christian We often use a simple approach where people design their experiments using rational multivariate design, but then simply use the best well that is found as the centre of the next round of experiments. This means that you don't have to score all the wells - which is

Re: [ccp4bb] How to improve crystal which is twinning?

2009-05-26 Thread Patrick Shaw Stewart
If you haven't already used it, I would certainly try the approach of microseeding into screens since you already have crystals http://scripts.iucr.org/cgi-bin/paper?S0907444907007652 -- patr...@douglas.co.uk mailto:patr...@douglas.co.uk Douglas Instruments Ltd. DouglasHouse,

[ccp4bb] Mr Bump

2009-05-26 Thread Thierry Granier
Dear all, I am testing Mr BUMP on vista and run into the following error message, after it has performed fasta and clustal alignements, it downloads several pdb files such as: PDB Download log: Chain:1qyc_B Download Log: Attempting to download the

[ccp4bb] MALLS equipment: SUMMARY

2009-05-26 Thread Marc Graille
Dear all, here is a summary of the few responses that I have got from my posting on MALLS equipment suggestions. 2 labs have WYATT miniDawn system. One is connected to an Agilent HPLC. Seems to be quite good. 1 lab has a Waters equipment connected to an Akta FPLC, which seems to be more

[ccp4bb] create cif for Zn atom

2009-05-26 Thread Raja Dey
Dear Friends, I have Zn atoms in my pdb file. So, I think I need to run elbow to create the cif otherwise refinement stops. I did the following and got the error as follows: phenix.elbow generate_easy_r4.pdb --do-all

[ccp4bb] Subject: off topic, purification from insect media and TFF/CFF

2009-05-26 Thread Mark Collins
Hey, I have a GST fusion protein secreted into express5 (with hint of serum), it does not bind beads. Changing pH with 4xPBS limits ppt and enables binding but in a scale up I think it makes sense to use a TFF/CFF setup for concentration and diafiltration. Does anybody have advice about

Re: [ccp4bb] Tips on fitting poorly defined loop regions

2009-05-26 Thread Lester Steven Guy Carter
Hi Drew, Sorry for the slightly late reply. Something that 'might' be able to help (though I fully agree with Dale's reply) is the procedure for local density improvement described here: Acta Cryst. (1997). D53, 540-543 Local Improvement of Electron-Density Maps. We are currently in the