- phenixbb - phenix-online.org

High B-factors and High Clash Score
by Edwin Lazo 24 Jul '15

24 Jul '15

Hi all, I am refining a structure that diffracted to 3.5 Angstroms and contains 6 monomers in the ASU. It is noteworthy to mention, in certain monomers, half their residues are missing (in other words no density). Initial b-factors after molrep were 118.585, R=0.32, and Rfree=0.40. Initial refinement was done with refmac and: mean b-value=117.344 R=0.31 Rfree=0.40 Refinement with Phenix (phenix-installer-dev-2054-intel-linux-2.6-x86_64-centos5) was performed and the Ramachandran plot was bad: OUTLIERS : 6.52 % ALLOWED : 13.67 % FAVORED : 79.82 % ROTAMER OUTLIERS : 7.18 % CBETA DEVIATIONS : 8 And final R=0.38 and Rfree=0.41. I then improved Ramachandran plot in coot and follow Pavel's suggestion: / - add H atoms: />>/ />>/ phenix.reduce model.pdb > model_H.pdb />>/ />>/ - then run a quick geometry regularization:*(**T**his part I**did in coot. phenix.**pdb**tools model_H.pdb --geom and phenix.pdbt**ools model_H.pdb --geometry**-**restraints do not work)* />>/ />>/ phenix.pdbtools model_H.pdb --geom />>/ />>/ - then strip off H: />>/ />>/ phenix.reduce -trim model_H_regularized.pdb > start.pdb />>/ />>/ - then run refinement using NCS and Ramachandran plot restraints: />>/ />>/ phenix.refine start.pdb def_data.mtz main.ncs=true --overwrite />>/ output.prefix=def2 main.number_of_mac=5 ramachandran_restraints=true />>/ rama_potential=emsley strategy=individual_sites+**individual_adp />>/ />>/ - then take outcome of previous refinement and run the same refinement />>/ plus weights optimization: />>/ />>/ phenix.refine def2_001.pdb def_data.mtz main.ncs=true --overwrite />>/ output.prefix=def3 main.number_of_mac=5 ramachandran_restraints=true />>/ rama_potential=emsley strategy=individual_sites+**individual_adp />>/ optimize_xyz=true nproc=6 /My current stats are as follows: Final R=0.35 Final Rfree=0.38 ALL-ATOM CLASHSCORE : 173.74 RAMACHANDRAN PLOT: OUTLIERS : 2.27 % ALLOWED : 4.61 % FAVORED : 93.13 % ROTAMER OUTLIERS : 36.26 % CBETA DEVIATIONS : 6 Wilson B-Value: 108.4 Mean B-value: 108.997 I am unsure how to proceed from here. I am planning on removing some side chains which have no density and then refining with Rama. restraints. I can also send my mtz and pdb if that would help. The stats when I processed the data are as follows from xia2 -3d (xds, xscale): High resolution limit 3.50 15.65 3.50 Low resolution limit 109.96 109.96 3.59 Completeness 94.1 90.5 91.5 Multiplicity 4.8 5.1 3.2 I/sigma 11.3 26.5 2.4 Rmerge 0.118 0.068 0.458 Rmeas(I) 0.144 0.080 0.605 Rmeas(I+/-) 0.144 0.083 0.584 Rpim(I) 0.062 0.036 0.311 Rpim(I+/-) 0.081 0.047 0.358 CC half 0.992 0.994 0.791 Wilson B factor 90.052 Anomalous completeness 86.9 93.6 71.3 Anomalous multiplicity 2.4 3.0 1.8 Anomalous correlation -0.262 -0.440 -0.052 Anomalous slope 1.005 0.000 0.000 Total observations 169836 2234 7765 Total unique 35071 442 2464 Assuming spacegroup: P 21 21 21 Unit cell: 73.010 180.780 219.910 90.000 90.000 90.000 Any help would greatly be appreciated, -- Edwin Lazo Scientific Associate Life Science and Biomedical Technology Research Resource National Synchrotron Light Source II Building 745 Upton, NY 11973 Office:(631)344-7247 Fax:(631)344-5059

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Posting to List
by Courtney Daczkowski 24 Jul '15

24 Jul '15

I would like to be able to post questions to all users. Thank you for your time, Courtney -- Courtney Marie Daczkowski ------------------------------------------------- PhD in Pharmacutical and Biomedical Science University of Georgia 2019 ------------------------------------------------- Masters in Biology Georgia Southern University 2014 ------------------------------------------------- Bachelors of Science James Madison University 2011

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Phenix GUI big reporting
by Nigel Moriarty 24 Jul '15

24 Jul '15

Folks One of the features of the Phenix GUI is the bug reporting which allows a user to send a program traceback. This allows the developers to zero in on the line that causes the problem but it is much easier if we have the inputs. This is why we ask that you include you email se we can work with you to resolve the problem ASAP. One of the weaknesses of the current system is that it relies on the user typing their email address correctly. If it is incorrect, we are sending replies that bounce. This happens occasionally and it's almost impossible to track the user down. We can also only assume, given that this misstyped user is sending in more reports, that he is getting frustrated. To that end, I'm naming names. If you typed in jwaning(a)umich.edu please contact us or fix the email in your preferences. Cheers Nigel --- Nigel W. Moriarty Building 33R0349, Physical Biosciences Division Lawrence Berkeley National Laboratory Berkeley, CA 94720-8235 Phone : 510-486-5709 Email : NWMoriarty(a)LBL.gov Fax : 510-486-5909 Web : CCI.LBL.gov

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Announcing the 2015 EMDataBank Map Challenge
by Cathy Lawson 23 Jul '15

23 Jul '15

Dear PhenixBB List Members, EMDataBank/Unified Data Resource for 3DEM is pleased to announce the 2015 Map Challenge. All members of the Scientific Community--at all levels of experience--are invited to participate as Challengers, and/or as Assessors. Seven benchmark raw image datasets have been selected for the challenge. Six are selected from recently described single 3D electron microscopy single particle structure determinations with image data collected as multi-frame movies; one is based on simulated (in silico) images. Challengers are sought to create single particle reconstructions from the targets, and then to upload their results with associated details. Assessors are sought to participate in evaluating submitted reconstructions. Registration is now open for all interested participants. Challengers may submit maps between August and December. Before submissions open, all are encouraged to provide feedback on submission requirements. An open assessment period will commence in early 2016. To learn more about this challenge and to register, please visit http://challenges.emdatabank.org and click on "MAP CHALLENGE" in the menu bar. The map challenge is the first of two community-wide challenges being sponsored by EMDataBank this year to critically evaluate 3DEM methods that are coming into use, with the ultimate goal of developing validation criteria associated with every 3DEM map and map-derived model. The second challenge, focused on creating coordinate models from 3DEM maps, will be announced later this year. Sincerely, Cathy Lawson on behalf of the EMDataBank Team and the Map Challenge Committee emdatabank.org www.facebook.com/emdatabank3dem

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Short contact with symmetry mate
by Ashok Nayak 23 Jul '15

23 Jul '15

Dear Phenix BB, I am refining a helical bundle structure where I have been obtaining an invariant short contact (close to 2A) at a Glu residue with Lys of symmetry related molecule of one helix of the bundle. I had been using Rigid body, TLS, occupancy and Indv ADP for the refinement (which gave the best Rfree values). If I include coordinate refinement the short contact seems to be gone rather with higher Rfree values. I ll appreciate some suggestions regarding this. Thank you in advance. Ashok Nayak CSIR-CDRI Lucknow, India

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NIH Request for Information about Technology Development
by Paul Adams 23 Jul '15

23 Jul '15

Dear Colleagues, my apologies for the slightly off-topic and US-centric posting, but I felt this was of sufficient interest to the structural biology community at large. The NIH, specifically the National Institute of General Medical Sciences, is in the process of considering how best to support the development of biomedical technologies, and access to those technologies. They have issued a request for information: http://grants.nih.gov/grants/guide/notice-files/NOT-GM-15-118.html This covers a very broad range of biomedical activities, including the development of new hardware and software for techniques such as NMR, crystallography, SAXS, and cryo-EM. It also includes the provision of technologies through facilities such as synchrotrons and other national research centers. For those of us in the US this provides an excellent, and rare, opportunity for researchers to voice their thoughts about how important technology development and national facilities are to the success of structural biology research. Please note that the deadline for response is August 7th. Cheers, Paul -- Paul Adams Deputy Division Director, Physical Biosciences Division, Lawrence Berkeley Lab Division Deputy for Biosciences, Advanced Light Source, Lawrence Berkeley Lab Adjunct Professor, Department of Bioengineering, U.C. Berkeley Vice President for Technology, the Joint BioEnergy Institute Laboratory Research Manager, ENIGMA Science Focus Area Building 33, Room 347 Building 80, Room 247 Building 978, Room 4126 Tel: 1-510-486-4225, Fax: 1-510-486-5909 http://cci.lbl.gov/paul Lawrence Berkeley Laboratory 1 Cyclotron Road BLDG 33R0345 Berkeley, CA 94720, USA. Executive Assistant: Louise Benvenue [ LBenvenue(a)lbl.gov ][ 1-510-495-2506 ] --

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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

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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

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Re: [phenixbb] pdb LINK record lost after phenix refine in GUI
by Pavel Afonine 17 Jul '15

17 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] >> >> >> > > >

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Map alignment
by Mullins, Elwood A. 17 Jul '15

17 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

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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

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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 ..................................................................

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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

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

15 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

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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

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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 --------------------------------------------

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Set up Simulated Annealing starting tempreture
by Xiao Lei 14 Jul '15

14 Jul '15

Dear Phenixbb members, I'm learning phenix this days. I use phenix refinement and found there is a simulated annealing option (SA Cartesian or SA torsion option). However, I found the SA cartesian starts at 5000K and SA torsion starts at 2500K by default, and I'd like to change the starting temperature by myself. I search phenix manual and found: To change starting SA temperature: % phenix.refine data.hkl model.pdb simulated_annealing=true \ strategy=individual_sites simulated_annealing.start_temperature=10000 I do not understand this, does this mean I have to type the above command in somewhere in phenix? is there a place I can simply put SA start temperature numbers in? Xiao

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NCS and R-Values Hung up at 0.42/0.46 for 2.1Å resolution
by John Bruning 11 Jul '15

11 Jul '15

I collected two datasets of the same ligand bound structure at 2.4 and 2.1 Å resolution. The apo structure has already been solved to 2.2Å resolution in P31 (and P3121 for SeMet). After processing each dataset as both P31 and P3121 in MOSFLM, I proceeded with MR with Phaser using sequential partial search models to place either 3 copies in the ASU for P3121, or 6 copies for P31. (The previously solved apo structure had 6 copies of the same protein in the ASU). *** in summary two datasets, processed as both P31 or P3121 After running xtriage for either .mtz, I get this warning about NCS: Distance to origin : 56.728 Height relative to origin : 26.388 % Translational pseudo-symmetry is very likely present in these data. Be aware that this will change the intensity statistics and may impact subsequent analyses, and in practice may lead to higher R-factors in refinement. Regardless, I can proceed with the MR using sequential partial search models to place either 3 copies (P3121) or 6 copies (P31) with decent solutions (i.e. packing looks good upon inspection, scoring looks appropriate -> SOLU SET RFZ=2.8 TFZ=8.3 PAK=13*LLG*=-37 *LLG*=2199 as an example). However, I did get the following somewhat expected warnings: Number of known components (1) not divisible by 2: Translational *NCS* correction not applied Large non-origin Patterson peak indicates that translational *NCS* is present Upon any attempt at initial refinement (with a number of different strategies), the R-factors are hung up > 0.42 (for example in the P3121, 2.1Å case): Start R-work = 0.4966, R-free = 0.5133; Final R-work = 0.4231, R-free = 0.4477 My concern is that there is some pathology that is not being recognized (merohedral twinning) or that the NCS/pseudosymmetry is not being addressed appropriately. -- Cheers, John

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Re: [phenixbb] Fwd: [ccp4bb] Phenix; converting a map to structure factors
by Pavel Afonine 11 Jul '15

11 Jul '15

Hi Mark, Tom copied me your email. > As I'm sure you are aware there is tremendous interest in building > into and refining against low resolution (by X-ray standards) EM maps. > Could you comment to the phenix BB about whether its appropriate to > convert maps to reciprocal space and use ML refinement? While it is a possible way of doing this (and this is how it's been done in the past) I don't think it is a good route to follow. In case of cryo-EM your data is map, so why not just refine against the map? Why take a detour through reciprocal-space by converting map into structure factors (=manipulating your original data) and doing reciprocal space using refinement programs that were designed for crystallography? With this in mind we have developed a new refinement tool in Phenix (it is still in active development!) called phenix.real_space_refine that is designed to refine atomic models directly into maps (any map: X-ray, neutron, cryo-EM, low or high resolution), for quick summary see http://phenix-online.org/presentations/real_space_refine.pdf as well as documentation page (at the bottom): http://phenix-online.org/documentation/ and newsletter article (page 43): http://phenix-online.org/newsletter/CCN_2013_07.pdf Let me know if you have any questions or comments! Pavel

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atom vdW dictionary for Python
by David Shin 11 Jul '15

11 Jul '15

Hi - I'm writing a Python script to measure the volume of pockets within protein structures - plus extra bells and whistles... thus a custom job. I was wondering just for speed, if someone could point me to values for van der Waals radii that are somewhat agreed upon for protein atoms, or if there is some dictionary already made that someone could point to that resides in phenix or some other structural biology package that would be ok for me to copy/use. Thanks, Dave

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Re: [phenixbb] [ccp4bb] Phenix; converting a map to structure factors
by Terwilliger, Thomas Charles 11 Jul '15

11 Jul '15

Hi Reza, Just use: phenix.map_to_structure_factors map.ccp4 d_min=2.5 or something like that, All the best, Tom T On Jul 10, 2015, at 11:27 AM, Reza Khayat wrote: Hi, Is it possible to convert a map to structure factors using Phenix? Thanks. Best wishes, Reza Reza Khayat, PhD Assistant Professor City College of New York Department of Chemistry New York, NY 10031

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NCS and R-Values Hung up at ~0.42/0.46
by John Bruning 11 Jul '15

11 Jul '15

Hi Everyone, I collected two datasets of the same ligand bound structure at 2.4 and 2.1 Å resolution. The apo structure has already been solved to 2.2Å resolution in P31 (and P3121 for SeMet). After processing each dataset as both P31 and P3121 in MOSFLM, I proceeded with MR with Phaser using sequential partial search models to place either 3 copies in the ASU for P3121, or 6 copies for P31. (The previously solved apo structure had 6 copies of the same protein in the ASU). *** in summary two datasets, processed as both P31 or P3121 After running xtraige for either .mtz, I get this warning about NCS: Largest Patterson peak with length larger than 15 Angstrom: Frac. coord. : 0.333 -0.333 -0.153 Distance to origin : 56.728 Height relative to origin : 26.388 % p_value(height) : 2.659e-03symmetry. Translational pseudo-symmetry is very likely present in these data. Be aware that this will change the intensity statistics and may impact subsequent analyses, and in practice may lead to higher R-factors in refinement. Regardless, I can proceed with the MR using sequential partial search models to place either 3 copies (P3121) or 6 copies (P31) with decent solutions (i.e. packing looks good upon inspection, scoring looks appropriate -> SOLU SET RFZ=2.8 TFZ=8.3 PAK=13*LLG*=-37 *LLG*=2199 as an example). However, I did get the following somewhat expected warnings: Number of known components (1) not divisible by 2: Translational *NCS* correction not applied Large non-origin Patterson peak indicates that translational *NCS* is present Upon any attempt at initial refinement (with a number of different strategies), the R-factors are hung up > 0.42 (for example in the P3121, 2.1Å case): Start R-work = 0.4966, R-free = 0.5133 Final R-work = 0.4231, R-free = 0.4477 *** best R-factors from ~ 15 different strategies My concern is that there is some pathology that is not being recognized (merohedral twinning) or that the NCS/pseudosymmetry is not being addressed appropriately. Any suggestions in troubleshooting this would be much appreciated, as I have pretty much exhausted everything I could think of. -- Cheers, John

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(no subject)
by Ashok Nayak 10 Jul '15

10 Jul '15

Dear Phenixites, I have a helical bundle structure, where in I wish to understand by what rotation and about which axis the dimers are inter-related. What I get from the superposition with Superpose is the transformation matrix and not the axis, and the angles are also elusive. Ashok Nayak CSIR-CDRI Lucknow, India --

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Axis of Rotation
by Ashok Nayak 10 Jul '15

10 Jul '15

Dear Phenixites, I have a helical bundle structure, where in I wish to understand by what rotation and about which axis the dimers are inter-related. What I get from the superposition with Superpose is the transformation matrix and not the axis, and the angles are also elusive. Thanks in advance -- Ashok Senior Research Fellow - Dr JV Pratap, Lab No-LSN 008 Molecular and Structural Biology Division Central Drug Research Institute, Janakipuram Extension Lucknow-226031 India

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rosetta.build_phenix_interface problem
by Appu kumar 10 Jul '15

10 Jul '15

Dear All, I have installed Rosetta on Linux machine. When i am issuing the command " rosetta.build_phenix_interface" it is giving me following error scons: Building targets ... scons: *** [build/src/release/linux/2.6/64/x86/gcc/4.4/python/libObjexxFCL.so] Implicit dependency `/usr/local/lib/libdl.so' not found, needed by target `build/src/release/linux/2.6/64/x86/gcc/4.4/python/libObjexxFCL.so'. scons: building terminated because of errors. Would you please give me your valuable suggestions to successfully carry out the Rosetta refinement. Thank you Appu

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