Re: [ccp4bb] How many is too many free reflections?

2015-06-10 Thread Axel Brunger
Dear Dusan, Following up on Gerard's comment, we also read your nice paper with great interest. Your method appears most useful for cases with a limited number of reflections (e.g., small unit cell and/or low resolution) resulting in 5% test sets with less than 1000 reflections in total. It

Re: [ccp4bb] Cross-validation when test set is miniscule

2014-12-20 Thread Axel Brunger
Dear Derek, I suggest you try 10% for the test set. You should still be able to judge the effect of various restraints (or constraints) as long as you keep the same test set. If you switch test sets, and re-refine, Rfree might change as much as 2% for a test set consisting of 200 reflections

[ccp4bb] Free Reflections as Percent and not a Number

2014-11-27 Thread Axel Brunger
We just had a chance to read this most interesting discussion. We would agree with Ian that jiggling or SA refinement may not be needed if refinement can in fact be run to convergence. However, this will be difficult to achieve for large structures, especially when only moderate to low

Re: [ccp4bb] High Rwork/Rfree vs. Resolution

2014-02-21 Thread Axel Brunger
Chris, First, I would try NCS restraints even at ~ 2 A. Second, any outliers in your diffraction data set that might skew the R values? Third, have you checked that your refined bulk solvent model is reasonable? Axel On Feb 21, 2014, at 6:13 PM, Chris Fage cdf...@gmail.com wrote: Thanks

Re: [ccp4bb] Why nobody comments about the Nobel committee decision?

2013-10-10 Thread Axel Brunger
minimization algorithm. I think I'm right about this. This was later adapted by Axel Brunger in Xplor and other progrmas followed. Cheers, Boaz הודעה מקורית מאת Alexander Aleshin aales...@sanfordburnham.orgmailto:aales...@sanfordburnham.org תאריך: 10/10/2013 0:07 (GMT+02

Re: [ccp4bb] Why nobody comments about the Nobel committee decision?

2013-10-10 Thread Axel Brunger
algorithm. I think I'm right about this. This was later adapted by Axel Brunger in Xplor and other progrmas followed. Cheers, Boaz הודעה מקורית מאת Alexander Aleshin aales...@sanfordburnham.orgmailto:aales...@sanfordburnham.org תאריך: 10/10/2013 0:07 (GMT+02:00) אל

[ccp4bb] postdoctoral positions available for experimental and computational methods for XFEL-based crystallography

2012-07-18 Thread Axel Brunger
characterization, novel sample delivery systems, data processing, experimental phasing, and refinement at low resolution. Extensive experience in computational or experimental crystallography is desirable. Candidates should submit a resume and a list of three references to Axel Brunger, Chair

Re: [ccp4bb] First images of proteins and viruses caught with an X-ray laser

2011-02-09 Thread Axel Brunger
I performed DEN-refinement with CNS using the same data and starting model, and obtained similar twinned R values and maps. The twin fraction is 0.5. Axel On Feb 9, 2011, at 3:29 PM, Jon Schuermann wrote: According to the paper, the data was refined in REFMAC in 'twin mode' which, I

Re: [ccp4bb] FW: [ccp4bb] Resolution and distance accuracies

2010-12-26 Thread Axel Brunger
We defined super-resolution in our DEN paper as achieving coordinate accuracy better than the resolution limit d_min of the diffraction data. We proposed this definition in analogy to its use wide-spread use in optical microscopy: super-resolution methods such as STORM, PALM, and STED achieve

Re: [ccp4bb] FW: [ccp4bb] Resolution and distance accuracies

2010-12-23 Thread Axel Brunger
Dear Gerard, Actually, for some of the tests we turned off the DEN network restraints for the last two refinement macrocycles, so, at least for these particular cases, the DEN method truly found a better minimum rather than forcing the system to the higher resolution structure. Cheers, Axel

[ccp4bb] Announcing CNS, version 1.3

2010-07-22 Thread Axel Brunger
== Announcing version 1.3 (general release) of the software: Crystallography NMR System (CNS) (copyright 1997-2010, Yale University) ==

Re: [ccp4bb] Compilation of CNS 1.21 on Mac OSX 10.6.3

2010-06-09 Thread Axel Brunger
, but so far there have been no updates of the Intel compilers to fix the problem with Xcode. Axel Brunger On Jun 9, 2010, at 11:35 AM, Ethan Merritt wrote: On Wednesday 09 June 2010 10:45:07 am James Holton wrote: I have often wondered how it is that one can actually run and play games like

Re: [ccp4bb] Compilation of CNS 1.21 on Mac OSX 10.6.3 - Solved

2010-06-09 Thread Axel Brunger
', making sure that /usr/local/path is in $PATH. With the Intel 11.1 compilers (and I used the evaluation version here), CNS compiles successfully, but fails on execution. Thanks to Axel Brunger and Benjamin Bardiaux, for sharing that the Intel fortran compiler is not compatible

Re: [ccp4bb] CNS: Composite omit map

2010-03-20 Thread Axel Brunger
I suggest you explicitly define the heterocompound as a rigid body for torsion dynamics. There are sometimes situations involving closed ring systems that cause this topology generation error. Axel Brunger On Mar 20, 2010, at 3:46 AM, Suman Tapryal wrote: Hi all, I am trying to calculate

[ccp4bb] Memorial Service for Warren DeLano

2010-01-21 Thread Axel Brunger
Begin forwarded message: From: Charles Wolfus cwol...@gmail.com Subject: Memorial Service for Warren DeLano In case you have not already heard, the DeLano family is having a memorial service for Warren: Sunday, February 7th @ 10am The Lucie Stern Center 1305 Middlefield Road Palo Alto,

Re: [ccp4bb] tr: Warren L Delano Memorial Award

2009-11-14 Thread Axel Brunger
not see the [ccp4bb] tag on it, so I pass it on. I think that this is important, since Warren has done so much for us all. I'll see how I can contribute (I hope it is easily done from abroad). Fred. Message du 15/11/09 01:09 De : Axel Brunger A : undisclosed-recipients:; Copie à : Objet

Re: [ccp4bb] Warren DeLano

2009-11-10 Thread Axel Brunger
Dear Linda, NSMB asked me and Jim Wells to write an obit for Warren. With your permission we would like to include a quote of your CCP4 posting (or a reference to it - depending what NSMB decides to do). Warren's words summarize so much how we call remember him. I hope you are doing well.

[ccp4bb] Warren DeLano

2009-11-05 Thread Axel Brunger
information as I receive it. Please join me in extending our condolences to Warren's family. Sincerely yours, Axel Brunger Axel T. Brunger Investigator, Howard Hughes Medical Institute Professor of Molecular and Cellular Physiology Stanford University Web:http://atbweb.stanford.edu Email

Re: [ccp4bb] unstable refinement

2009-02-16 Thread Axel Brunger
Dear Ian, I totally agree with your observations and recommendations. If one is concerned about instability of the optimizer (minimization and/or simulated annealing) I suggest to also monitor the value of the total energy function (X-ray maximum likelihood term plus all restraints). Another

Re: [ccp4bb] Crystallographic computing platform recommendations?

2008-11-18 Thread Axel Brunger
Brian, There is one disadvantage with using AFP rather than wide open (potentially insecure) NFS mounts. Remote login via ssh into a client computer won't by default mount the user's AFP home directory. While it is possible to manually mount the AFP home directory it may preclude other

Re: [ccp4bb] FW: [ccp4bb] X-Ray versus NMR Structure

2008-11-18 Thread Axel Brunger
-publication manuscript is available on my website, publication section. Axel Brunger On Nov 14, 2008, at 3:13 PM, Boaz Shaanan wrote: oops, I forgot to give the reference: Science (1992), vol. 257, p. 961 Boaz Axel T. Brunger Web:http://atbweb.stanford.edu Email: [EMAIL

Re: [ccp4bb] Refinement using Phenix

2008-11-15 Thread Axel Brunger
, but this is dependent on the particular case. Thus, it's useful to compute both types of maps. I don't see the need to compute a composite annealed omit map every time you make a change in model, though. Axel Brunger On Nov 15, 2008, at 10:34 AM, Priya Mudgal wrote: Dear All, I have a general question

Re: [ccp4bb] CNS refinement problem

2008-09-06 Thread Axel Brunger
This sounds to me like a compiler problem on your machine. Try using the latest Intel Ifort, Portland Group pgf95, or GFORTRAN compiler. Axel Brunger On Sep 12, 2008, at 2:56 AM, jxqi wrote: Dear ccp4bbs, When I was refining a protein structure using the rigid.inp in CNS(Version 1.21

[ccp4bb] openmp version of CNS 1.21

2008-07-23 Thread Axel Brunger
, so there will be some small differences between the single and multi- processor versions. The only changes compared to the single processor version of CNS 1.21 are in a few source files, the Makefile compilation files, the test output files, and the executable cns file. Axel Brunger Axel

[ccp4bb] Version 1.21 of the Crystallography and NMR System (CNS)

2008-07-11 Thread Axel Brunger
CNS 1.21 is now available. A particular highlight is automatic dimensioning of torsion angle dynamics arrays (e.g., MAXTREE), so no user intervention is needed anymore. There are many bug fixes in source code, modules, and input files. I would like to thank Joe Krahn, Ben Eisenbraun, and

Re: [ccp4bb] Stack trace terminated abnormally. cns_solve on macosx leopard

2008-05-21 Thread Axel Brunger
There is an operating system bug in mac osx 10.5.x that may cause this problem if you are running the program with input redirection, but without output redirection, i.e., cns test.inp and the input file contains one ore more blank lines. try: cns test.inp test.out Axel Brunger

Re: [ccp4bb] density_modify.inp is not running in cns1.2 but runs in cns1.1

2008-04-23 Thread Axel Brunger
I certainly have not experienced this problem with our pre-compiled Intel version for mac os X that is available when downloading CNS 1.2 from the CNS website. Axel On Apr 23, 2008, at 7:59 AM, William Scott wrote: Could one or both of you try this with the pre-compiled intel version that

Re: [ccp4bb] an over refined structure

2008-02-08 Thread Axel Brunger
In such cases, we always define the test set first in the high-symmetry space group choice. Then, if it is warranted to lower the crystallographic symmetry and replace with NCS symmetry, we expand the test set to the lower symmetry space group. In other words, the test set itself will be

Re: [ccp4bb] an over refined structure

2008-02-07 Thread Axel Brunger
resolution, for example). Axel Brunger On Feb 7, 2008, at 9:57 AM, Dean Madden wrote: Hi Dirk, I disagree with your final sentence. Even if you don't apply NCS restraints/constraints during refinement, there is a serious risk of NCS contaminating your Rfree. Consider the limiting case

Re: [ccp4bb] low-res cutoff in refinement

2008-01-24 Thread Axel Brunger
Are you using CNS 1.2? This version has a robust bulk solvent model and anisotropic correction that is much improved compared to CNS 1.1. It is similarly robust as that of Phenix (although different in detail). Axel Brunger Van Den Berg, Bert wrote: Hi all, during refinement of our

Re: [ccp4bb] low-res cutoff in refinement

2008-01-24 Thread Axel Brunger
wrote: No, we have been using version 1.1 so far. Thanks for the suggestion, we'll use version 1.2 from now on and try Phenix as well. Bert -Original Message- From: Axel Brunger [mailto:[EMAIL PROTECTED] Sent: Thu 1/24/2008 7:35 PM To: Van Den Berg, Bert Cc: CCP4BB@JISCMAIL.AC.UK

Re: [ccp4bb] Extraction of test set from CNS reflection file

2007-03-01 Thread Axel Brunger
original test set selection. If you continue to have trouble, please contact me directly with more details. Axel Brunger Florian Brückner wrote: Dear colleagues, I have a dataset form a protein-ligand complex. I want to use the same Rfree test set for refinement as used for the protein