Re: [ccp4bb] Reasoning for Rmeas or Rpim as Cutoff

2012-01-30 Thread Dunten, Pete W.
Frank, Don't you already get a plot of SigmaA versus resolution from refmac, where the free set of reflections has been used to estimate SigmaA? Have a look at some of your log files. Pete From: CCP4 bulletin board [CCP4BB@JISCMAIL.AC.UK] On Behalf Of Fra

[ccp4bb] 5BrU

2012-01-13 Thread Dunten, Pete W.
Does anyone have the dictionary file for BrU, as in the brominated ribonucleotide? The distributed files include the deoxy version, 5-bromo-2'-deoxyuridine-5'-monophosphate. Best wishes, Pete

Re: [ccp4bb] detect dsDNA

2011-09-30 Thread Dunten, Pete W.
Try the program DIBER to evaluate the likelihood your crystal contained ordered nucleic acid in addition to protein. See Acta Cryst. (2010). D66, 643-653 “DIBER: protein, DNA, or both?” by G. Chojnowski & M. Bochtler. Good luck, Pete From: CCP4 bulletin

Re: [ccp4bb] Radiation damage with crystals containing metal centers (TaBr people chime in?)

2010-10-04 Thread Dunten, Pete W.
Regarding backsoaking [2], This is one of those nice exercises for the reader! Try raddose calculations with versus without 1 mM heavy-atom compound in the solvent channels. Pete -Original Message- From: CCP4 bulletin board [mailto:ccp...@jiscmail.ac.uk] On Behalf Of Francis E Reyes Se

Re: [ccp4bb] Introducing PDBprints - salient, at-a-glance info about PDB entries

2010-07-15 Thread Dunten, Pete W.
I like the species icon for 2cbr, human crabp in your list http://xray.bmc.uu.se/gerard/structures_pdbprints.html. Is it something from Greek mythology? From: CCP4 bulletin board [ccp...@jiscmail.ac.uk] On Behalf Of Gerard DVD Kleywegt [ger...@xray.bmc.uu.

Re: [ccp4bb] how to improve Rfree?

2009-10-19 Thread Dunten, Pete W.
But see Acta Crystallogr D Biol Crystallogr. 2006 Mar;62(Pt 3):227-38. Epub 2006 Feb 22. on why thin shells aren't necessarily the answer. And note neither program mentioned, dataman nor sftools, will allow you to extend the set of shells to higher resolution if you want to follow the practice o

Re: [ccp4bb] Rfactor got stuck with a data having alternate strong and weak reflections.

2009-09-03 Thread Dunten, Pete W.
Hi Eleanor, Are you sure about the application of twinning tests to look for lattice-translocation defects? In twins the intensities sum, but in lattice translocation cases, the domains can be so small that you can't simply sum intensities . . . at least that's how I interpret http://www.am

[ccp4bb] Reading the old literature / truncate / refinement programs

2008-09-25 Thread Dunten, Pete W.
I mentioned previously phenix.refine tosses your weak data if IMEAN, SIGIMEAN are chosen during refinement. I'm wondering if this omission of weak Fobs from the Fobs-Fcalc difference map explains why the difference maps out of refmac seem to be more helpful in showing where to move atoms.

[ccp4bb] More on truncate ignorance

2008-09-18 Thread Dunten, Pete W.
I hadn't realized phenix.refine handles this differently. If I start with an mtz file from truncate, with F, SIGF, IMEAN, SIGIMEAN all available, the default for phenix.refine seems to be to work with IMEAN, SIGIMEAN. >From the log file . . . Intensities converted to amplitudes for use in refi

Re: [ccp4bb] Ammonium citrate tribasic buffer

2008-08-09 Thread Dunten, Pete W.
Bill, You still lose a point for missing the fourth pKa in ammonium citrate, the ammonium ion. Kind regards, Pete -Original Message- From: CCP4 bulletin board on behalf of William G. Scott Sent: Sat 8/9/2008 12:09 PM To: CCP4BB@JISCMAIL.AC.UK Subject: Re: [ccp4bb] Ammonium citrate triba

Re: [ccp4bb] Expression vector with NdeI-ClaI sites

2008-07-21 Thread Dunten, Pete W.
May be old fashioned, but what about cut with ClaI, fill in, and then you have a blunt end to work with. -Original Message- From: CCP4 bulletin board [mailto:[EMAIL PROTECTED] On Behalf Of Artem Evdokimov Sent: Sunday, July 20, 2008 12:02 PM To: CCP4BB@JISCMAIL.AC.UK Subject: Re: [ccp4bb]

Re: [ccp4bb] Question re: ice rings in diffraction data

2008-07-15 Thread Dunten, Pete W.
Look at the "reject fraction" keyword and increase the value, as described on pp 39-40 of the manual Pete From: CCP4 bulletin board [mailto:[EMAIL PROTECTED] On Behalf Of Mona Rahman Sent: Tuesday, July 15, 2008 7:14 AM To: CCP4BB@JISCMAIL.AC.UK Subject: [ccp4bb

Re: [ccp4bb] pdbset bug - seqres record

2008-07-10 Thread Dunten, Pete W.
Is this just a consequence of old/new conventions for the SEQRES records? If so, send a feature request to ccp4, asking for an option to be added to pdbset. Pete -Original Message- From: CCP4 bulletin board [mailto:[EMAIL PROTECTED] On Behalf Of Ed Pozharski Sent: Thursday, July 10, 200

Re: [ccp4bb] Are Calcium Citrate Crystals A Common False Positive?

2008-04-29 Thread Dunten, Pete W.
And how will you know if they are the calcium citrate xtals Sam asked about, and not sodium citrate xtals? Sodium citrate in the Hampton Crystal Screen condition will crystallize out at 4 degrees. It's solubiility is pH and temperature dependent. You'll need to go to your friendly neighborhood

Re: [ccp4bb] just how bad can phases be and still help

2007-09-08 Thread Dunten, Pete W.
Here's one - FOM > 0.5 after shelxe, SAD phases, not traceable Lots of weak data, as truncate shows . . . Analysis of mean intensity by parity for reflection classes For each class, Mn(I/sig(I)) is given for even and odd parity with respect to the condition, eg group 1: h even & odd; group

Re: [ccp4bb] The importance of USING our validation tools

2007-08-16 Thread Dunten, Pete W.
A few thoughts following on Richard Baxter and George Sheldrick . . . Re: gaps in the lattice – see the tyr-tRNA synthase structures (1tya for example). Fersht has written a whole book full of insights from these structures. Re: Phaser Z scores. For some MR work with two xtal forms of a str

Re: [ccp4bb] DANO from PDB

2007-06-07 Thread Dunten, Pete W.
And just to be complete . . . Solve will calculate data with the anomalous component for you, although you can't stop it from adding some "experimental" error. Phenix.refine is another option. Pete

Re: [ccp4bb] journals with on-hold policy

2007-02-19 Thread Dunten, Pete W.
If you publish the paper a year from now, with no hold, will everyone be happy? -Original Message- From: CCP4 bulletin board on behalf of [EMAIL PROTECTED] Sent: Fri 2/16/2007 6:54 AM To: CCP4BB@JISCMAIL.AC.UK Subject: [ccp4bb] journals with on-hold policy Dear CCP4ers, This is a new qu