Re: [ccp4bb] AutoXDS

2011-03-03 Thread Tim Gruene
Dear Marco, I did not know autoxds, but google suggests that it is a csh(uarrrgh)-script from SLAC. So as long as you have some c-Shell installed on your MAC, to script should execute. Maybe you can be more precise about what you mean by your last sentence to get more accurate help. Cheers, Tim

Re: [ccp4bb] while on the subject of stereo

2011-03-03 Thread Sergei Strelkov
Dear Dave, Here come my five pence... I personally found stereo graphics useful in two cases. 1. When you first introduce students to biomolecular structure and/or biocrystallography. Showing stereo certainly helps 'building up' the initial fascination, which is very important of course. But

Re: [ccp4bb] Problem with refinement and positive electron density

2011-03-03 Thread Eleanor Dodson
I think you have been caught by a new REFMAC feature which tries to design its own TLS groups including linked H2Os and ligands. Check your tls output records and see what it has clustered into a group.. I am not sure how to disable this - at times I want to override any automatic

Re: [ccp4bb] Is there any program for specifically calculating Rvalue in CCP4

2011-03-03 Thread Eleanor Dodson
On 03/03/2011 06:13 AM, Ting-Wei Jiang wrote: Dear all experts, I'm trying to calculate R-value (and free R) specifically which is between data and the modified structure(refined by myself without help from any program).I've looked the program for calculating a long while.Actually,I found one

[ccp4bb] Scientific Programmer Position

2011-03-03 Thread SHEPARD William
Dear All, Please find below an announcement for a Scientic Programmer on the PROXIMA 2 beamline at Synchrotron SOLEIL. The position is a 2-year contract suitable for a PXer with strong computing instrumentation skills or a Computing Engineer.

[ccp4bb] I/sigmaI of 3.0 rule

2011-03-03 Thread Roberto Battistutta
Dear all, I got a reviewer comment that indicate the need to refine the structures at an appropriate resolution (I/sigmaI of 3.0), and re-submit the revised coordinate files to the PDB for validation.. In the manuscript I present some crystal structures determined by molecular replacement using

Re: [ccp4bb] I/sigmaI of 3.0 rule

2011-03-03 Thread Eleanor Dodson
No - and I dont think it is accepted practice now either.. I often use I/SigI 1.5 for refinement.. Look at your Rfactor plots from REFMAC - if they look reasonable at higher resolution use the data Eleanor On 03/03/2011 11:29 AM, Roberto Battistutta wrote: Dear all, I got a reviewer

Re: [ccp4bb] I/sigmaI of 3.0 rule

2011-03-03 Thread Mischa Machius
Roberto, The reviewer's request is complete nonsense. The problem is how to best and politely respond so as not to prevent the paper from being accepted. Best would be to have educated editors who could simply tell you to ignore that request. Since this issue comes up quite often still, I

Re: [ccp4bb] I/sigmaI of 3.0 rule

2011-03-03 Thread John R Helliwell
Dear Roberto, As indicated by others in reply to you the current best practice in protein crystallography is not a rigid application of such a cut off criterion. This is because there is such a diverse range of crystal qualities. However in chemical crystallography where the data quality from such

Re: [ccp4bb] Problem with refinement and positive electron density

2011-03-03 Thread Judith Reeks
Dear Eleanor, I don't think that was the case. I add tlsd waters exclude to a refinement which as I understand it should prevent that. Also, I checked the output files and the TLS groups only involve my protein, waters and ligands aren't included anywhere. I can't explain why my TLS

Re: [ccp4bb] Is there any program for specifically calculating Rvalue in CCP4

2011-03-03 Thread Ed Pozharski
On Thu, 2011-03-03 at 14:13 +0800, Ting-Wei Jiang wrote: I'm trying to calculate R-value (and free R) specifically which is between data and the modified structure(refined by myself without help from any program). At long last, someone escaped the tyranny and oppression of the refinement

Re: [ccp4bb] I/sigmaI of 3.0 rule

2011-03-03 Thread Ed Pozharski
On Thu, 2011-03-03 at 12:29 +0100, Roberto Battistutta wrote: Does anyone know the origin or the theoretical basis of this I/sigmaI 3.0 rule for an appropriate resolution? There is none. Did editor ask you to follow this suggestion? I wonder if there is anyone among the subscribers of this bb

Re: [ccp4bb] while on the subject of stereo

2011-03-03 Thread Ed Pozharski
On Wed, 2011-03-02 at 19:23 -0500, David Roberts wrote: What I am really looking for is an answer to a simple question in that is stereo a nice thing from a pedagogy standpoint for showing students complex biomolecules. Of course it is. Exactly how much excitement it generates among the

Re: [ccp4bb] I/sigmaI of 3.0 rule

2011-03-03 Thread Van Den Berg, Bert
There seem to be quite a few rule followers out there regarding resolution cutoffs. One that I have encountered several times is reviewers objecting to high Rsym values (say 60-80% in the last shell), which may be even worse than using some fixed value of I/sigI. On 3/3/11 9:55 AM, Ed

Re: [ccp4bb] stuck with COOT installation in openSUSE 11.3

2011-03-03 Thread Paul Emsley
On 02/28/2011 09:39 PM, Hena Dutta wrote: I could not open the COOT GUI after installing either from 'coot-0.6.1-binary-Linux-x86_64-centos-5-gtk2.tar.gz' or from 'coot-0.6.2-pre-1-revision-3205-binary-Linux-x86_64-centos-5-gtk2.tar.gz' I have managed to build a coot pre-release for

Re: [ccp4bb] I/sigmaI of 3.0 rule

2011-03-03 Thread Vellieux Frederic
For myself, I decide on the high resolution cutoff by looking at the Rsym vs resolution curve. The curve rises, and for all data sets I have processed (so far) there is a break in the curve and the curve shoots up. To near vertical. This inflexion point is where I decide to place the high

Re: [ccp4bb] I/sigmaI of 3.0 rule

2011-03-03 Thread Jim Pflugrath
As mentioned there is no I/sigmaI rule. Also you need to specify (and correctly calculate) I/sigmaI and not I/sigmaI. A review of similar articles in the same journal will show what is typical for the journal. I think you will find that the I/sigmaI cutoff varies. This information can be used

Re: [ccp4bb] I/sigmaI of 3.0 rule

2011-03-03 Thread Phil Evans
My preferred criterion is the half-dataset correlation coefficient output by Scala (an idea stolen from the EM guys): I tend to cut my data where this falls to not less than 0.5. The good thing about this is that it is independent of the vagaries of I/sigma (or rather of the SD estimation) and

Re: [ccp4bb] I/sigmaI of 3.0 rule

2011-03-03 Thread Bernhard Rupp (Hofkristallrat a.D.)
I think this suppression of high resolution shells via I/sigI cutoffs is partially attributable to a conceptual misunderstanding of what these (darn) R-values mean in refinement versus data merging. In refinement, even a random atom structure follows the Wilson distribution, and therefore, even

Re: [ccp4bb] I/sigmaI of 3.0 rule

2011-03-03 Thread Ed Pozharski
On Thu, 2011-03-03 at 16:02 +0100, Vellieux Frederic wrote: For myself, I decide on the high resolution cutoff by looking at the Rsym vs resolution curve. The curve rises, and for all data sets I have processed (so far) there is a break in the curve and the curve shoots up. To near

Re: [ccp4bb] I/sigmaI of 3.0 rule

2011-03-03 Thread Ed Pozharski
On Thu, 2011-03-03 at 08:08 -0700, Bart Hazes wrote: I don't know what has caused this wave of high I/Sigma threshold use but here are some ideas It may also be related to what I feel is recent revival of the significance of the R-values in general. Lower resolution cutoffs in this context

Re: [ccp4bb] I/sigmaI of 3.0 rule

2011-03-03 Thread Van Den Berg, Bert
Does the position of this inflection point depend on the redundancy? Maybe it does not; for high-redundancy data one would simply get a much higher corresponding Rsym. On 3/3/11 11:13 AM, Ed Pozharski epozh...@umaryland.edu wrote: On Thu, 2011-03-03 at 16:02 +0100, Vellieux Frederic wrote:

Re: [ccp4bb] I/sigmaI of 3.0 rule

2011-03-03 Thread Ed Pozharski
On Thu, 2011-03-03 at 09:34 -0600, Jim Pflugrath wrote: As mentioned there is no I/sigmaI rule. Also you need to specify (and correctly calculate) I/sigmaI and not I/sigmaI. A review of similar articles in the same journal will show what is typical for the journal. I think you will find

Re: [ccp4bb] I/sigmaI of 3.0 rule

2011-03-03 Thread Bernhard Rupp (Hofkristallrat a.D.)
related to what I feel is recent revival of the significance of the R-values because it's so handy to have one single number to judge a highly complex nonlinear multivariate barely determined regularized problem! Just as easy as running a gel! Best BR -Original Message- From:

Re: [ccp4bb] I/sigmaI of 3.0 rule

2011-03-03 Thread Vellieux Frederic
Hi, I don't think XDS generates an Rpim value, does it? The XDS CORRECT strep provides the old fashioned Rsym (R-FACTOR) plus R-meas and Rmrgd-F. The curves look all the same though Fred. Ed Pozharski wrote: On Thu, 2011-03-03 at 16:02 +0100, Vellieux Frederic wrote: For myself, I

Re: [ccp4bb] Is there any program for specifically calculating Rvalue in CCP4

2011-03-03 Thread Pavel Afonine
Hi, - phenix.fmodel will probably output it too or maybe there is some phenix.get_me_my_damn_rfactor or such as Eric pointed out earlier, the command phenix.model_vs_data model.pdb data.mtz will do exactly this. Pavel. P.S.: phenix.fmodel is the tool to compute total model structure

Re: [ccp4bb] I/sigmaI of 3.0 rule

2011-03-03 Thread Ronald E Stenkamp
Discussions of I/sigma(I) or less-than cutoffs have been going on for at least 35 years. For example, see Acta Cryst. (1975) B31, 1507-1509. I was taught by my elders (mainly Lyle Jensen) that less-than cutoffs came into use when diffractometers replaced film methods for small molecule work,

Re: [ccp4bb] I/sigmaI of 3.0 rule- do not underestimate gels

2011-03-03 Thread Felix Frolow
Well BR, do not underestimate complexity of running a gel! There are even more harsh referees comments on gel appearance and quality than comments on cutting data based on R,RF and sigmaI :-) Especially when one is trying to penetrate into prestigious journals... Dr Felix Frolow Professor of

Re: [ccp4bb] I/sigmaI of 3.0 rule

2011-03-03 Thread Maia Cherney
Dear Bernhard I am wondering where I should cut my data off. Here is the statistics from XDS processing. Maia SUBSET OF INTENSITY DATA WITH SIGNAL/NOISE = -3.0 AS FUNCTION OF RESOLUTION RESOLUTION NUMBER OF REFLECTIONS COMPLET R-FACTOR R-FACTOR COMPARED I/SIGMA R-meas Rmrgd-F Anomal SigAno

Re: [ccp4bb] I/sigmaI of 3.0 rule

2011-03-03 Thread Simon Phillips
I take the point about a tendency in those days to apply sigma cutoffs to get lower R values, which were erroneously expected to indicate better structures. I wonder how many of us remember this paper by Arnberg et al (1979) Acta Cryst A35, 497-499, where it is shown for (small molecule)

Re: [ccp4bb] I/sigmaI of 3.0 rule

2011-03-03 Thread Maia Cherney
I have to resend my statistics. Maia Cherney wrote: Dear Bernhard I am wondering where I should cut my data off. Here is the statistics from XDS processing. Maia On 11-03-03 04:29 AM, Roberto Battistutta wrote: Dear all, I got a reviewer comment that indicate the need to refine the

Re: [ccp4bb] I/sigmaI of 3.0 rule- do not underestimate gels

2011-03-03 Thread Bernhard Rupp (Hofkristallrat a.D.)
there are even more harsh referees comments on gel appearance and quality than comments on cutting data based on R,RF and sigmaI :-) Especially when one is trying to penetrate into prestigious journals... Ok I repent. For improving gels there is the same excellent program, also useful for

Re: [ccp4bb] I/sigmaI of 3.0 rule

2011-03-03 Thread Van Den Berg, Bert
We should compile this discussion and send it as compulsive reading to journal editors...;-) Bert On 3/3/11 12:07 PM, Simon Phillips s.e.v.phill...@leeds.ac.uk wrote: I take the point about a tendency in those days to apply sigma cutoffs to get lower R values, which were erroneously

Re: [ccp4bb] I/sigmaI of 3.0 rule

2011-03-03 Thread Jacob Keller
When will we finally jettison Rsym/Rcryst/Rmerge? 1. Perhaps software developers should either not even calculate the number, or hide it somewhere obscure, and of course replacing it with a better R flavor? 2. Maybe reviewers should insist on other R's (Rpim etc) instead of Rmerge? JPK PS is

Re: [ccp4bb] Problem with refinement and positive electron density

2011-03-03 Thread Ethan Merritt
On Thursday, March 03, 2011 05:10:02 am Judith Reeks wrote: Dear Eleanor, I don't think that was the case. I add tlsd waters exclude to a refinement which as I understand it should prevent that. Also, I checked the output files and the TLS groups only involve my protein, waters and

Re: [ccp4bb] I/sigmaI of 3.0 rule

2011-03-03 Thread Bernhard Rupp (Hofkristallrat a.D.)
First of all I would ask a XDS expert for that because I don't know exactly what stats the XDS program reports (shame on me, ok) nor what the quality of your error model is, or what you want to use the data for (I guess refinement - see Eleanor's response for that, and use all data). There is one

[ccp4bb] [Fwd: Re: [ccp4bb] I/sigmaI of 3.0 rule]

2011-03-03 Thread Maia Cherney
Original Message Subject:Re: [ccp4bb] I/sigmaI of 3.0 rule Date: Thu, 03 Mar 2011 10:43:23 -0700 From: Maia Cherney ch...@ualberta.ca To: Oganesyan, Vaheh oganesy...@medimmune.com References: 2ba9ce2f-c299-4ca9-a36a-99065d1b3...@unipd.it

Re: [ccp4bb] I/sigmaI of 3.0 rule

2011-03-03 Thread Roberto Battistutta
just to clarify that, at least in my case, my impression is that the editor was fair, I was referring only to the comment of one reviewer. Roberto Roberto Battistutta Associate Professor Department of Chemistry University of Padua via Marzolo 1, 35131 Padova - ITALY tel. +39.049.8275265/67

Re: [ccp4bb] I/sigmaI of 3.0 rule

2011-03-03 Thread Maia Cherney
I see, there is no consensus about my data. Some people say 2.4A, other say all. Well, I chose 2.3 A. My rule was to be a little bit below Rmerg 100%. At 2.3A Rmerg was 98.7% Actually, I have published my paper in JMB. Yes, reviewers did not like that and even made me give Rrim and Rpim etc.

Re: [ccp4bb] I/sigmaI of 3.0 rule

2011-03-03 Thread Maksymilian Chruszcz
Dear All, Relatively recent statistics on I/sigmaI and Rmerge in PDB deposits are presented in two following publications: 1.Benefits of structural genomics for drug discovery research. Grabowski M, Chruszcz M, Zimmerman MD, Kirillova O, Minor W. Infect Disord Drug Targets. 2009 Nov;9(5):459-74.

Re: [ccp4bb] I/sigmaI of 3.0 rule

2011-03-03 Thread Tim Gruene
Hello Maia, Rmerge is obsolete, so the reviewers had a good point to make you publish Rmeas instead. Rmeas should replace Rmerge in my opinion. The data statistics you sent show a mulltiplicity of about 20! Did you check your data for radiation damage? That might explain why your Rmeas is so

Re: [ccp4bb] I/sigmaI of 3.0 rule

2011-03-03 Thread Bernhard Rupp (Hofkristallrat a.D.)
The data statistics you sent show a mulltiplicity of about 20! Did you check your data for radiation damage? That might explain why your Rmeas is so utterly high while your I/sigI is still above 2 (You should not cut your data but include more!) So then I got that wrong - with that *high* a

Re: [ccp4bb] I/sigmaI of 3.0 rule

2011-03-03 Thread Bernhard Rupp (Hofkristallrat a.D.)
Rmeas is always higher than Rmerge, so if my Rmerg is high I don't like Rmeas either. But that makes perfect sense now per Tim: the linear Rmerge gives for small N (lower redundancy) always lower values and rises with redundancy to approach Rmeas/rim for high redundancy. I like the idea just

[ccp4bb] setting up additive screen

2011-03-03 Thread m zhang
Dear all, I am trying to optimize my crystal with additives. Since the yield of my protein purification is very limited, I am wondering what is the most efficient way to set up drops with additive to save my protein and not wasting additives? I am setting up 1 to 1 drops with 0.2 ul

[ccp4bb] AKTA Explorer and Prime need new homes [off-topic]

2011-03-03 Thread Erin Curry
Hello CCP4BB, We have a beautiful GE AKTA Explorer and an AKTA Prime available. Please contact me directly at ress...@gmail.com or 510-344-6633 for more info. Thanks, Erin

Re: [ccp4bb] I/sigmaI of 3.0 rule

2011-03-03 Thread Bernhard Rupp (Hofkristallrat a.D.)
I don't like Rmeas either. Given the Angst caused by actually useful redundancy, would it not be more reasonable then to report Rpim which decreases with redundancy? Maybe Rpim in an additional column would help to reduce the Angst? BR Maia Tim Gruene wrote: Hello Maia, Rmerge is

Re: [ccp4bb] I/sigmaI of 3.0 rule

2011-03-03 Thread Bart Hazes
higher redundancy lowers Rpim because it increases precision. However, it need not increase accuracy if the observations are not drawn from the true distribution. If pathologic behaviour of Rfactor statistics is due to radiation damage, as I believe is often the case, we are combining

Re: [ccp4bb] setting up additive screen

2011-03-03 Thread Yibin Lin
Use robot. You only need 0.1ul*96=9.6ul of protein solution. On Thu, Mar 3, 2011 at 7:59 PM, m zhang mzhang...@hotmail.com wrote: Dear all, I am trying to optimize my crystal with additives. Since the yield of my protein purification is very limited, I am wondering what is the most

[ccp4bb] mosflm gain

2011-03-03 Thread Bryan Lepore
wondering if mosflm can automatically estimate the gain. i.e. i gather it is still estimated the usual way. -Bryan

Re: [ccp4bb] Processing Laue data

2011-03-03 Thread marius . schmidt
Based on roughly 1500 complete Laue data sets containing more than 45000 Laue patterns, I can say the following: How to collect Laue data? 1.) put crystal on (capillary or cryo is fine) 2.) switch on X-rays (or Neutrons) for time-resolved studies select one or more pulses else forget

Re: [ccp4bb] Processing Laue data

2011-03-03 Thread marius . schmidt
Dear John, of course you are right, apologies for my little exaggeration. Warmest regards Marius Dear Marius, To these two centres to which you refer we can add:- Diamond Light Source; contact person Prof David Allan (small molecule Laue X-ray crystallography); Institut Laue Langevin ;

Re: [ccp4bb] mosflm gain

2011-03-03 Thread David Waterman
Usually Mosflm will use a default value for the gain that depends on the type of detector used. This value is not realistic for CCD detectors, that is it is not really equal to the ratio of ADUs to incident X-ray photons, however it satisfies typical images under the assumptions of pixel

Re: [ccp4bb] I/sigmaI of 3.0 rule

2011-03-03 Thread Ingo P. Korndoerfer
not sure whether this option has been mentioned before ... i think what we really would like to do is decide by the quality of the density. i see that this is difficult. so, short of that ... how about the figure of merit in refinement ? wouldn't the fom reflect how useful our data really are ?