- phenixbb - phenix-online.org

histidine flip in refinement
by Joel Tyndall 22 Jul '15

22 Jul '15

Hi all, We are trying to optimise a histidine interaction where NE2 would ideally make a hydrogen bond with an adjacent tyrosine hydroxyl. The starting point contains the hydrogen bond. However upon refinement the ring flips (chi2 x 180 degrees) to place the CE1 adjacent to the tyrosine hydroxyl. Is it possible to stop this as I see no reason why phenix.refine would want to do this Regards Joel _________________________________ Joel Tyndall, PhD Associate Professor in Medicinal Chemistry National School of Pharmacy University of Otago PO Box 56 Dunedin 9054 New Zealand Skype: jtyndall Ph: +64 3 479 7293

5 8

Newest phenix version for Unix cluster
by Xiao Lei 20 Jul '15

20 Jul '15

Hi All, I'd like to download the newest phenix version ( 1.10pre-2104 July13th2015 nightly build) and install it on HPC cluster (Unix system). Is CentOS 5 ok for my purpose? It seems for a 64bit linux this is the only download option: 64-bit Linux (Intel/AMD) Kernel 2.6 (64-bit; CentOS 5) [ download command-line installer ] Thanks ahead. Xiao

1 0

Re: [phenixbb] pdb LINK record lost after phenix refine in GUI
by Pavel Afonine 16 Jul '15

16 Jul '15

Hi Lu, could it be that you define a conflicting restraint? On one hand you want that O-C bond to be 1.44A (that's what I see on your picture), on the other hand you want that H to be reasonable distance apart from O (and not 1.14A). I would guess if you want to define that bond you nee to delete H first. Could this explain what you observe? Pavel On 7/16/15 18:38, luzuok wrote: > Dear Pavel, > Thank you for your explanation. > After adding the bond restrain and refinement, the position of the > hydrogen from the bonded atom of the ligand seems not reasonable. This > hydrogen is too close to the other bonded atom. I can even see this H > atom links to two atom. > It seems that the riding H of C23 cannot see the OG neighbouring > to it. > > Best wishes! > Lu > > > -- > 卢作焜 > 南开大学新生物站A202 > > Lu Zuokun, Ph.D. Candidate > College of Life Science, Nankai University > > At 2015-07-16 23:07:49, "Pavel Afonine" <pafonine(a)lbl.gov > <mailto:[email protected]>> wrote: > > Hi Lu, > > seeing the link in graphics and actually having bond defined in > refinement are two different things. Refinement uses standard > restraints and those you define on top of that. Visualization > tools use standard bonding patterns to show you the bonds (and > sometimes also use distance based connectivity, such as Pymol). > Visualization tools are unlikely to guess anything on top of that. > > So if you want to have specific bond in refinement, then tell > refinement program to add it (and checking .geo file is not a bad > idea to verify that it was actually added). Seeing that bond on > graphics is a different story and it is outside the scope of > Phenix refinement. Check documentation of visualization program > you use to learn what's required to see what you want to see. > > Pavel > > On 7/16/15 00:54, luzuok wrote: >> >> Dear Pavel and Nigel, >> >> I can see: >> >> bond pdb=" OG SER A 265 " >> pdb=" C23 AIX A 700 " >> ideal model delta sigma weight residual >> 1.330 1.339 -0.009 2.00e-01 2.50e+01 2.16e-03 >> >> I think this bond is what I want. >> >> If I want to _see_ this bond in graphical tool, like coot or >> pymol, Do I have to add a link record in PDB? >> >> You are right Nigel, I made a mistake of python and Phenix version. >> >> Best withes! >> Lu >> >> -- >> >> Lu Zuokun, Ph.D. Candidate >> College of Life Science, Nankai University >> >> 在 2015-07-16 14:21:24，"Pavel Afonine" <pafonine(a)lbl.gov> 写道： >> >> All connectivity information is in .geo file: check it to see >> if the bind in question is present there. >> phenix.refine does not read/write LINK records given that all >> info is in .geo file, and input (custom) linking is specified >> via custom bonds using atom selection syntax (or clicking in >> the GUI). >> >> Pavel >> >> On 7/15/15 18:04, luzuok wrote: >>> Dear all, >>> Although Custom geometry restrains was added (see log). >>> After phenix refine, the link record was lost and there seem >>> no bond between this two atoms (1.44 angstrom). >>> Do you think this is a real bond? How to maintain this record? >>> Any comment is appreciated! >>> Best regards! >>> >>> Data resolution: 2.4 >>> Phenix version:v2.7 >>> >>> phenix refine log: >>> ======================== Summary of geometry restraints >>> ======================= >>> >>> Number of disulfides: simple=1, symmetry=0 >>> Simple disulfide: pdb=" SG CYS A 482 " - pdb=" SG CYS >>> A 484 " distance=2.04 >>> Custom bonds: >>> bond: >>> atom 1: "ATOM 1205 OG SER A 265 .*. O " >>> atom 2: "HETATM 3413 C23 AIX A 700 .*. C " >>> symmetry operation: x,y,z >>> distance_model: 1.339 >>> distance_ideal: 1.330 >>> ideal - model: -0.009 >>> slack: 0.000 >>> delta_slack: -0.009 >>> sigma: 0.2000 >>> Total number of custom bonds: 1 >>> Time building geometry restraints manager: 0.20 seconds >>> >>> pdb file LINK record: >>> LINK OG SER A 265 C23 AIX A 700 >>> 1555 1555 >>> >>> >>> -- >>> >>> Lu Zuokun, Ph.D. Candidate >>> College of Life Science, Nankai University >>> >>> >>> >>> >>> _______________________________________________ >>> phenixbb mailing list >>> phenixbb(a)phenix-online.org >>> http://phenix-online.org/mailman/listinfo/phenixbb >>> Unsubscribe:[email protected] >> >> >> > > >

2 2

Map alignment
by Mullins, Elwood A. 16 Jul '15

16 Jul '15

All, Is it possible to align two structures and two maps without moving both to a P1 box? This seems to be the default, if not the only, option in Structure Comparison and Superpose Maps. Thank you, Elwood Elwood A. Mullins, Ph.D. <> elwood.mullins(a)vanderbilt.edu<mailto:[email protected]> <> tel 615.936.5234 <> fax 615.343.6707

3 2

pdb LINK record lost after phenix refine in GUI
by luzuok 16 Jul '15

16 Jul '15

Dear all, Although Custom geometry restrains was added (see log). After phenix refine, the link record was lost and there seem no bond between this two atoms (1.44 angstrom). Do you think this is a real bond? How to maintain this record? Any comment is appreciated! Best regards! Data resolution: 2.4 Phenix version:v2.7 phenix refine log: ======================== Summary of geometry restraints ======================= Number of disulfides: simple=1, symmetry=0 Simple disulfide: pdb=" SG CYS A 482 " - pdb=" SG CYS A 484 " distance=2.04 Custom bonds: bond: atom 1: "ATOM 1205 OG SER A 265 .*. O " atom 2: "HETATM 3413 C23 AIX A 700 .*. C " symmetry operation: x,y,z distance_model: 1.339 distance_ideal: 1.330 ideal - model: -0.009 slack: 0.000 delta_slack: -0.009 sigma: 0.2000 Total number of custom bonds: 1 Time building geometry restraints manager: 0.20 seconds pdb file LINK record: LINK OG SER A 265 C23 AIX A 700 1555 1555 -- Lu Zuokun, Ph.D. Candidate College of Life Science, Nankai University

2 3

phenix.superpose_ligands
by cedric bauvois 16 Jul '15

16 Jul '15

Dear all, I would like to superimpose a small organic compound (file format sdf) on a small peptide (file format pdb). Is there a way to use phenix.superpose_ligands to this ? thank you for your help Cédric -- .................................................................. Dr. Cedric Bauvois Cristallographie des protéines Institut de Recherches Microbiologiques J.-M. Wiame -IRMW Campus CERIA - Av. E. Gryson, 1 B-1070 Bruxelles, BELGIUM e-mail: Cedric.Bauvois(a)ulb.ac.be tél: +32 (0)2 5273634 fax: +32 (0)2 5267273 ..................................................................

2 1

simulated annealing composite omit map or iterative build composite omit map at 2.7A resolution
by Xiao Lei 15 Jul '15

15 Jul '15

Dear Phenixbb members, I am thinking of generating a composite omit map for my whole structure model (the model is solved by phaser MR in CCP4 and refined by phenix.refine program, results of phenix.refine shows Rfree/Rwork is 27% / 20%. The resolution of data is 2.7A). From previous phenix posts and information from internet, I know there are four composite omit map types in Phenix: "simple"; "refine"; "simulated annealing" and "iterative build" composite omit map. Because I want to get rid of model bias as much as possible, I am thinking of choosing either "simulated annealing" or "iterative build" method, though I know it needs much longer time to run. I know "iterative build" composite map option is more powerful to get rid of model bias as I found in phenix manual that "A more powerful approach is to generate an "iterative-build" omit map (Terwilliger et al. 2008), which rebuilds the structure instead of annealing." But at the "autobuild-iterative guild omit map" manual it also said "The AutoBuild Wizard produces a refined model that can be nearly complete if the data are strong and the resolution is about 2.5 A or better. At lower resolutions (2.5 - 3 A) the model may be less complete and at resolutions > 3A the model may be quite incomplete and not well refined." My questions are: 1. As the resolution of my data is 2.7A, does this mean Simulated annealing composite map option is better for me in this case? 2. Inside phenix panel, there are two map tools for generating composite omit map, one is "Composite omit map" tool and the other is "Autobuild-iterative build omit map" tool. I tried the "composite omit map" tool with simulated annealing option with my refined model and original x-ray data, in the output file I only get 2mFo-DFc map (I know this is by default) but no pdb output, I am guessing this is because in this "composite omit map" tool my model is not modified (or refined) by the program, just the composite omit map is generated, am I right? If I am right, does this mean the following step is to open the output map in coot with my model, and do manual adjustment of the model in the regions which does not fit the map? 3. In the "autobuild-iterative build omit map" tool, there is also an option of "simulated annealing" composite omit map, is this option the same as the "simulated annealing" option in the "composite omit map" tool and will give the same output (just the 2mFo-DFc map by default, not modifying my model) ? 4. If I use iterative-build composite map with this 2.7A resolution, I'm guessing I will get a modified or refined pdb model output and a composite 2mFo-DFc map, but my model may not be complete because of the resolution, does this mean I have to manually add the missing part of model in the following step? 5. Is there an option to generate composite omit mFo-DFc map along with composite 2mFo-Fc map at the same time? Thanks ahead. Xiao

1 0

The difference of using data label "Imean and SigImean" or "F and SigF" in Phenix
by Xiao Lei 14 Jul '15

14 Jul '15

Dear All, I am using Phenix1.9-1962 version on Mac OS X 10.10.3. I notice in Phenix refinement or composite omit map GUI panel, there is an option for me to select data labels. I have two options of data labels: one is "Imean and SigImean"; the other is "F and SigF". My experimental data is from a single crystal diffraction set, after convert scale file (.sca) to mtz file using scalepack2mtz in ccp4, I have a mtz file output. I checked the mtz file using viewhkl program, it shows I have both Imean, SigImean, and F, SigF columns. Is there any difference between the data label choices in these phenix programs? Xiao

2 2

message after refinement
by Almudena Ponce Salvatierra 14 Jul '15

14 Jul '15

Dear all, after refinement of my nucleic acid structure with phenix.refine I get: "warning: rms deviation from ideal geometry (bonds and/or angles) is suspisciously high. You may need to optimize X-ray stereochemistry weighting" However when I move to the molprobity tab I see no outliers no anything... looking weird. I even more wonder where this comes from because the fact is that I had one refinement with no warnings or anything and today I repeated the same, exactly the same, except for the fact that I renumbered one of the chains. Now all out of a sudden (I know it doesn't sound scientific at all), I get this warning regarding the rmsd when I was actually considering that the refinement stage was over. Does anybody have a theory regarding where the problem might be here? Thanks a lot in advance. Best wishes, Almudena -- Almudena Ponce-Salvatierra Macromolecular crystallography and Nucleic acid chemistry Max Planck Institute for Biophysical Chemistry Am Fassberg 11 37077 Göttingen Germany

2 1

Refinement with new mtz.file
by Aleksandar Bijelic 14 Jul '15

14 Jul '15

Dear CCP4 user and experts, I refined (with PHENIX) a 3.0 A dataset obtaining Rfree of about 0.24 (with good geometry according to Ramachandran, Beta Outliers, etc.) .... Everything seems to be ok (especially in relation to the resolution) .... because the mtz.file I used was quite old and I cannot find my xscale.hkl file, I processed the data set again (this time with optimizng and polishing) and received a "better" file according to almost everything (resolution limit, I/sigma, CC(1/2), Rmeas), thus I used this new mtz.file and put it in my last refinement step (the refinement which led to the above mentioned Rfree = 0.24). Suprisingly, the refinement starts at Rwork = 0.18 and Rfree = 0.19 but ending up with 0.20 and 0.22, respectively. So I wanted to know if this is usual? I was expecting my data to become slightlly better but what is irritating me is the starting R-values of the refinement and that it get worse during refinement. Maybe I did something wrong? Is it reasonable to replace the mtz.file with a new one in the last refinement step or should I start the refinement from the scratch? In the sake of completeness, I deleted the header of the used pdb.file because of the R-flag error which occurs, since Phenix reconizes that the pdb.file was already used with other Rflags. Sorry, but I am still a beginner in this field, so I would be very grateful if somebody could explain me this situation and my mistake and if I need to start refinement from the beginning. Thank you in advance! Best Regards. Aleksandar -- ------------------------------------------- Aleksandar Bijelic, MSc. Institut für Biophysikalische Chemie Universität Wien Althanstrasse 14 A-1090 Wien Tel: +43 1 4277 52536 e-Mail: aleksandar.bijelic(a)univie.ac.at --------------------------------------------

7 10