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Re: [phenixbb] Different cell content than expected in Xtriage
by Singh, Bishal 19 Aug '15

19 Aug '15

Dear Folmer, Thank you very much for your words. Yes! I refined the model after molecular replacement. Electron density is nicely defined for all residues including their side chains. There is no extra electron density. All refinement parameters are fine. Rwork and Rfree are around 22% and 25%, respectively. The model that I used for phaser was a homology model generated from a structure with 60 % sequence identity to my protein. I prefer to use homology model than providing sequence identity in phaser because I think that the local structural errors are more precisely defined in homology models. Thanking you again! Kind regards, Bishal From: Folmer Fredslund <folmerf(a)gmail.com<mailto:[email protected]>> Date: Tue, 18 Aug 2015 15:34:23 +0200 To: noro <b.singh(a)dkfz-heidelberg.de<mailto:[email protected]>> Subject: Re: [phenixbb] Different cell content than expected in Xtriage Hi Bishal, Did you try to refine the model from phaser? Did you check the packing of the 2 molecules? Did you look at the electron density from phaser and see if some of it could look like an extra molecule? It is not impossible to have 70% solvent content, so I don't think you should be too worried, just investigate the result. You probably have another molecule there, phaser was just not able to find it, but you should be able to manually fit it easily. Btw, how similar is your model to your own protein? Hope this helps Folmer Fredslund 2015-08-18 15:02 GMT+02:00 Singh, Bishal <b.singh(a)dkfz-heidelberg.de<mailto:[email protected]>>: Dear all, I am solving crystal structure of a protein of size 33.7kDa in space group P 43 21 2 at 2.25 Å resolution. Unit cells constants are 121.51 121.51 156.6 90 90 90. The cell content analysis in Xtriage showed 1050 residues (~ 3X 33.7 kDa) per ASU with 50 % solvent content, whereas the molecular replacement in mr-phaser produced a dimer (2X 33.7 kDa). When we consider a dimer per ASU, it should have approximately 70 % solvent content. Please suggest me whether solution is right or not. I shall appreciate your opinions. Kind regards, Bishal _______________________________________________ phenixbb mailing list phenixbb(a)phenix-online.org<mailto:[email protected]> http://phenix-online.org/mailman/listinfo/phenixbb Unsubscribe: phenixbb-leave(a)phenix-online.org<mailto:[email protected]> -- Folmer Fredslund

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Coot mutation of Asp residue to isoAsp residue
by Xiao Lei 19 Aug '15

19 Aug '15

Dear Phenixbb members, I suspect one Asp residue in my model may be an isoAsp (isomerization of Asp). I am asking if there is way to mutate Asp residue to isoAsp(isoaspartic acid) residue in coot GUI (I'm using coot 0.8.1 EL in Mac OS X10.10.5)? I know there is a mutation button on coot, but the mutated aa lists are all natural amino acids. If I have to delete the Asp residue first and then build isoAsp into the density map, is there a way in coot to build an isoAsp residue in map? Thanks ahead. Xiao

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Different cell content than expected in Xtriage
by Singh, Bishal 18 Aug '15

18 Aug '15

Dear all, I am solving crystal structure of a protein of size 33.7kDa in space group P 43 21 2 at 2.25 Å resolution. Unit cells constants are 121.51 121.51 156.6 90 90 90. The cell content analysis in Xtriage showed 1050 residues (~ 3X 33.7 kDa) per ASU with 50 % solvent content, whereas the molecular replacement in mr-phaser produced a dimer (2X 33.7 kDa). When we consider a dimer per ASU, it should have approximately 70 % solvent content. Please suggest me whether solution is right or not. I shall appreciate your opinions. Kind regards, Bishal

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"Table 1" wavelength
by mohamed noor 17 Aug '15

17 Aug '15

Dear all A trivial question but just to be sure: For a structure phased and built using MR-SAD with a dataset collected at one wavelength and refined with a higher-resolution dataset at a different wavelength, how should the wavelength be reported in "Table 1"? And what if the higher-resolution dataset is not isomorphous to the anomalous dataset? Is it sensible to do MR-SAD first, redo MR with the better dataset against the MR-SAD model and then refine at the higher resolution (about 0.8 A better)? Thanks.

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Post-doctoral position in Structural Biology at the Goethe-University Frankfurt, Germany
by Maike Bublitz 14 Aug '15

14 Aug '15

Dear all, please find below a job announcement posted on behalf of my colleague Jun. Prof. Inga Hänelt at the Goethe-University Frankfurt: The Structural Biology of Membrane Transporters group of Inga Hänelt, Institute of Biochemistry at the Goethe University in Frankfurt am Main invites a post-doctoral researcher to join the Emmy Noether project “Determinants of ion channel versus transporter mechanism in the K(+) transporter superfamily“. The project is in need of a candidate with strong biochemical skills for membrane protein purification and/or experience in protein crystallization. If you are interested in further information please follow the link below. http://biochem.uni-frankfurt.de/fileadmin/user_upload/MechanismsMembraneTra… <http://biochem.uni-frankfurt.de/fileadmin/user_upload/MechanismsMembraneTra…> Contact Information for this post: Dr. Inga Hänelt Juniorprofessor for Biochemistry Institute of Biochemistry, Biocenter N220/1.03 Goethe-University Frankfurt Max-von-Laue-Str. 9 60438 Frankfurt Phone: 0049-69-798-29261 Fax: 0049-69-798-29495 Email: Haenelt(a)biochem.uni-frankfurt.de <mailto:[email protected]> -- Dr. Maike Bublitz Department of Biochemistry, Biocenter Goethe University Frankfurt Max-von-Laue-Str. 9 60438 Frankfurt am Main Germany phone: +49 (0)69 798 29274 bublitz(a)em.uni-frankfurt.de <mailto:[email protected]>

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on b factor refine for phenix.real_space_refine
by Smith Lee 14 Aug '15

14 Aug '15

Dear All, I first run a default phenix.real_space_refine with the map and initial model, with the model got, I run phenix.real_space_refine with run=adp, I find for the second phenix.real_space_refine step with run=adp, it can gives a reasonable value of b-factors for each residues in the model, and it cannot modify the coordinates of any atoms in the model (in comparison with the model got by the default phenix.real_space_refine in the first step). I just read a Nature paper from David Baker group "Atomic-accuracy models from 4.5-Å cryo-electron microscopy data with density-guided iterative local refinement", it says "Because cryo-EM maps are frequently better in resolution in some regions than others, atomic B factors are fit against cryo-EM density data to maximize the real-space correlation between model and map". For Real-space B-factor refinement, the math functions used by that Nature paper include, ( f is a scattering factor fit to each element) My question is, does b-factor refine only give a reasonable b-factor to each atom or residue in the model (so that we know the displacement of each atom or residue), or besides giving reasonable b-factor, it can also change and optimize the x y z coordinates of each atom in the model, and the phenomenon I observed in phenix.real_space_refine on that it only gives reasonable b-factor without modification of the x y z coordinates was only limited to the case I see in phenix.real_space_refine? Best regards. Smith

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Strong anomalous signal but AutoSol fails
by mohamed noor 11 Aug '15

11 Aug '15

Dear developers I have a low resolution anomalous dataset which Aimless suggests has an effective resolution to 3.3 A and anomalous signal to 3.5 A. However, SAD phasing with AutoSol is not successful with the final R factor around 50 %. I also have another dataset collected at a remote wavelength without anomalous signal to 3 A but they are not isomorphous (> 2 A difference in c axis). The anomalous signal comes from the ligand heme c, which is bound covalently to the protein, so its occupancy should be 1. The protein is quite small with about 120 residues. Xtriage suggests an NCS of 6 to 20 with most likely number to be 13. Is there any reason why a reasonable solution cannot be found? There is no twinning. I am using the latest nightly 1.10 pre2124. Thanks.

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ligand refinement
by xinghuaqin＠126.com 11 Aug '15

11 Aug '15

Hi everyone, I am refining a structure of protein/ligand complex (2.75 Å) almost to the last stage. However, I found that some atoms of the ligand is too close to the protein (1.2 or 1.3 Å) after refinement. How should I avoid this? Should I use the "nonbonded_distance_cutoff" parameter? What the value should be set to? Another question is that at this resolution is it possible for me to refine the occupancy? Any suggestion is appreciated. Best Xinghua Xinghua Qin Ph.D Department of Physiology The Fourth Military Medical University 169# Changlexi Road Xi'an 710032, China Tel. 86-29-84772779 E-mail: xinghuaqin(a)126.com

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Re: [phenixbb] anomalous difference map calculation
by Ashok Nayak 11 Aug '15

11 Aug '15

Alexandra Marques <at.marques(a)fct.unl.pt> wrote: >_______________________________________________ >phenixbb mailing list >phenixbb(a)phenix-online.org >http://phenix-online.org/mailman/listinfo/phenixbb >Unsubscribe: phenixbb-leave(a)phenix-online.org

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Failed ADP refinement with active TLS and weight optimization
by Schubert, Carsten [JRDUS] 10 Aug '15

10 Aug '15

Hi, I am running into some strange issues with regards to ADP refinement especially when I am putting final touches on a structure for PDB submission. The problem manifests itself most prominent in the B-factor refinement of solvent, but also maps are affected and are becoming noisier, so I assume this problem affects the protein as well. I checked this against the current release 1.9 and the latest pre1.10 dev version, both versions show the issue. Refinement protocol includes individual_xyz, individual_adp, TLS and weight optimization. The problem I am running into is that the ADP of waters only changes by a global offset. The problem is tricky to spot but more evident when looking at solvent placed in coot with the default ADP (30). The ADP changes only by a global offset, no individual refinement takes place. Since the protein is refined by TLS the problem is not as evident, but as mentioned the fofc maps get noisier from cycle to cycle even though no manual change to the geometry was performed. To me an indicator that the B-factors are not refined properly. The problem can be circumvented by reverting back to isotropic B-factors and then refine with weight refinement for 5-10 cycles. After that TLS can be switched back on for a final polishing cycle. In stubborn cases I had to randomly assign B-factors close to Wilson-B and refine for more cycles to get out of the hole I refined myself into. Another indicator that something went awry is the weight refinement for the B-factors: ----------Individual ADP refinement---------- R-FACTORS <Bi-Bj> <B> WEIGHT TARGETS work free delta data restr 20.66 26.39 5.73 5.712 67.871 2.160 5.225 20.66 26.38 5.73 5.712 67.871 0.030 5.225 20.66 26.38 5.73 5.712 67.871 0.125 5.225 20.66 26.38 5.73 5.712 67.871 0.500 5.225 20.66 26.38 5.73 5.712 67.871 1.000 5.225 20.66 26.38 5.73 5.712 67.871 1.500 5.225 20.66 26.38 5.73 5.712 67.871 2.000 5.225 20.66 26.38 5.73 5.712 67.871 2.500 5.225 20.66 26.38 5.73 5.712 67.871 3.000 5.225 20.66 26.38 5.73 5.712 67.871 3.500 5.225 20.66 26.38 5.73 5.712 67.871 4.000 5.225 20.66 26.38 5.73 5.712 67.871 4.500 5.225 20.66 26.38 5.73 5.712 67.871 5.000 5.225 Essentially there is no change in R/Rfree with regards to different weights. I have not figured out the exact time point when this happens during the course of the refinement but it seems to be coupled to using TLS in combination with ADP refinement and during the final stages of the refinement. I can provide data offline to reproduce the issue Cheers, Carsten

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Sulfur SAD
by mohamed noor 07 Aug '15

07 Aug '15

Dear all Would you have some tips on collecting datasets for S-SAD at a 'normal' beamline (tunable from 0.5-2.5 A)? How helpful/important is it to use mini kappa? Thanks.

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fedora 22 phenix 1.9 installation
by Agnieszka Kiliszek 06 Aug '15

06 Aug '15

Dear All, I want to install new phenix 1.9 but I got error: ========================================================================= PHENIX Installation version: 1.9 release tag: 1692 machine type: intel-linux-4.1.3-200.fc22.x86_64-x86_64 source machine type: intel-linux-4.1.3-200.fc22.x86_64-x86_64 OS version: linux user shell: /bin/bash destination: /usr/local ========================================================================= =============================== ERROR =================================== intel-linux-4.1.3-200.fc22.x86_64-x86_64 is not a supported platform, installation aborted use the --try-unsupported option to attempt installation on this platform use the --no-gui option for a core PHENIX installation =============================== ERROR ======================= It looks like I have double x86_64 in the machine type and it doesn't want to install phenix. Using --try-unsupported gives me these: ~/phenix-installer-1.9-1692/bundles/bundle-1.9-1692-intel-linux-4.1.3-200.fc22.x86_64-x86_64.tar.gz neither source nor binary available, exiting installation. In these folder I have file bundle-1.9-1692-intel-linux-4.1.3-200.fc22.x86_64.tar.gz so I have changed name to bundle-1.9-1692-intel-linux-4.1.3-200.fc22.x86_64-x86_64.tar.gz but again got error finding installed versions finding binary versions cat: build/intel-linux-4.1.3-200.fc22.x86_64-x86_64/version: No such file or directory no pre-existing binary components detected installing new binary package configuring PHENIX components I checked log and got these: /home/gusia/programy/phenix-installer-1.9-1692/bin/install-from-binary: line 359: /usr/local/phenix-1.9-1692/build/intel-linux-4.1.3-200.fc22.x86_64-x86_64/base/bin/python: No such file or directory What can I do to install phenix? Agnieszka

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R vs Geometry (branched off from: [ccp4bb] Rfree at low resolution: how reliable is it, really?)
by Keller, Jacob 03 Aug '15

03 Aug '15

Dear Crystallographers, In following the thread on Rfree reliability, and in the context of a structure I am currently polishing, I have started to wonder what is the ideal way to weight geometry versus R values. I had always thought the rationalization for using geometric restraints was actually to help R values to decrease eventually, since the truth about one’s protein structure is much more likely to agree with the thousands of molecules already solved than with the particularities of the model one has built or the reflection data under consideration. What happens, though, when one’s R values are, say, 2% or even 5% lower with less weight on geometry? It seems to me that this is a gray area, and it would be great to have some sort of general rule. I know that Phenix has a weight-optimization protocol which uses parallel runs with different weights, but I am curious what method is used to decide which one was best? There may not, however, be such a general rule, since I suppose this question is one we always encounter in science. For example, in fitting a few data points, when does one abandon the use of a linear model in favor of something more sophisticated? Or maybe, indeed, someone *has* discovered some reasonable way of approaching this? All the best, Jacob Keller

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symmetry file for Phenix merging statistics
by Xiao Lei 03 Aug '15

03 Aug '15

Hi Phenixbb members, I am trying to use "phenix merging statistics" tool, and I have an unmerged sca file from HKL2000, because the unmerged HKL2000 output does not have unit cell information, so I also need to input a symmetry file, how can I find the symmetry file? Is there a way to generate a symmetry file? Thanks ahead. Xiao

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Anisotropic B-factors with Trucated Data
by Keller, Jacob 02 Aug '15

02 Aug '15

Dear Crystallographers, I have a dataset which was artificially truncated at 1.7 Ang by the limitations of our setup, but the resolution is probably 1.5 Ang or so. I would like to try running anisotropic B refinement in Phenix, but am not sure how to tweak to get this to happen. I know about the parameter:measurement ratio concept, but I think it may still be better than isotropic. NB the dataset is also 42% twinned. All the best, Jacob Keller ******************************************* Jacob Pearson Keller, PhD Looger Lab/HHMI Janelia Research Campus 19700 Helix Dr, Ashburn, VA 20147 email: kellerj(a)janelia.hhmi.org *******************************************

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Radiation-sensitive dataset and molecular replacement
by mohamed noor 31 Jul '15

31 Jul '15

Dear all I have a crystal that diffracted to about 3.5 A for the first 5 degrees and rapidly decayed after that. With xia2, I can get a good dataset to 6 A (CC1/2, I/sigma etc.) using all the frames. I can also process the first good frames with obviously low completeness (20%). As I only want to check if molecular replacement can be done before investing time on experimental phasing (not expecting miracles here and not publishing this yet), should I bother running Phaser? The closest search model only covers about 20 % of the protein with 20 % identity. Thanks.

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Berkeley Server Downtime
by Paul Adams 30 Jul '15

30 Jul '15

Dear Colleagues, as part of final commissioning of our new building there will be a power outage to the Computational Crystallography Initiative server room. As a result several structural biology web services will be offline for a short while. These include: - The Phenix web site (http://phenix-online.org/) - The DIALS West web site (http://dials.lbl.gov/) - The CCI web site (http://cci.lbl.gov/) - The Structural Biology Technology Portal (http://technology.sbkb.org/) The servers will be shutdown at 5pm Pacific time on Thursday 30th (i.e. tonight). Services should resume by the morning of Friday August 31st. During the downtime bug reports and emails requesting help should be queued and received by us once the servers are back online. We greatly appreciate your understanding, and hope that this doesn’t present too much of an inconvenience. 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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Re: [phenixbb] mr_rosetta pause & resume
by Juergen Koepke 30 Jul '15

30 Jul '15

Dear Tom, I found in the phenixbb exactly my case discribed as you wrote on July 22nd, 2013 on reply of Morten Grøftehauge: Hi Morten, Yes, you'll need to specify the start_point (otherwise it will start from the beginning considering the solutions you have in the .pkl file along with ones that it finds along the way). I don't know if rosetta3.5 makes a difference in mr_rosetta; I'd be happy to hear from anyone on this. All the best, Tom T but unfortunately after launching the command "phenix.mr_rosetta mr_rosetta_params.eff start_point=rosetta_rescore mr_rosetta_solutions=./rebuild_results.pkl" I get the following error message: Sorry: Unable to create temporary directory MR_ROSETTA_3 Error message is: The directory MR_ROSETTA_3 could not be created (it may already exist) but this looks not logical to me since I am in directory MR_ROSETTA_3 because I want to restart were the program stopped after the crash. Do I have to restart the program from within another directory or what ist the trick? I must admit I first started without the start_point=rosetta_rescore until I realized the program had started my job from the very beginning. Thus i killed the processes again and tried the above with the start_point included. Has my previous attempt already confused something? __________________________________ Dr. Juergen Koepke Project Leader ESFRI-Instruct Core Centre Max-Planck-Inst. of Biophysics Dept. Molecular Membrane Biol. Max-von-Laue Str. 3 D-60438 Frankfurt/Main Germany T: [49] 69 6303 1055 F: [49] 69 6303 1002 C: [49] 151 2263 6736 Email: juergen.koepke(a)biophys.mpg.de URL: https://registration.cc.biophys.mpg.de

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Re: [phenixbb] Extract coordinates from PDB file
by Zhijie Li 30 Jul '15

30 Jul '15

With a little modification it can be more specific ;) : grep -e '.\{12\} CA .\{61\}C' 1PRW.pdb But not so ideal for multi-model NMR structures: grep -e '.\{12\} CA .\{61\}C' 1cff.pdb Zhijie -----Original Message----- From: Pavel Afonine Sent: Wednesday, July 29, 2015 5:59 PM To: Tanner, John J. ; phenixbb(a)phenix-online.org ; Ashok Nayak Subject: Re: [phenixbb] Extract coordinates from PDB file John, that may include Calcium or similarly called atoms in ligands -;) But if you know there are none in your structure then your solution would do the job and much faster! Pavel On 7/29/15 14:53, Tanner, John J. wrote: > grep " CA " file.pdb > ca.pdb > > Sent from Jack's iPhone > >> On Jul 29, 2015, at 4:15 PM, Pavel Afonine <pafonine(a)lbl.gov> wrote: >> >> Hi, >> >>> I wish to extract xyz coordinates of Calpha atoms from the PDB file of >>> my interest. >>> Is there a program in Phenix or CCP4 for the same? >> some examples: >> >> - this will select all CA atoms: >> >> phenix.pdb_atom_selection model.pdb "name CA" >> >> - this will select CA atoms in chain A and chain B: >> >> phenix.pdb_atom_selection model.pdb "name CA and (chain A or chain B)" >> >> - this will select all Carbon atoms: >> >> phenix.pdb_atom_selection model.pdb "element C" >> >> - this will select all atoms with alternative conformation id A: >> >> phenix.pdb_atom_selection model.pdb "altloc A" >> >> etc etc etc - this can be very detailed and flexible. >> >> Pavel >> _______________________________________________ >> phenixbb mailing list >> phenixbb(a)phenix-online.org >> http://phenix-online.org/mailman/listinfo/phenixbb >> Unsubscribe: phenixbb-leave(a)phenix-online.org > _______________________________________________ > phenixbb mailing list > phenixbb(a)phenix-online.org > http://phenix-online.org/mailman/listinfo/phenixbb > Unsubscribe: phenixbb-leave(a)phenix-online.org _______________________________________________ phenixbb mailing list phenixbb(a)phenix-online.org http://phenix-online.org/mailman/listinfo/phenixbb Unsubscribe: phenixbb-leave(a)phenix-online.org

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Extract coordinates from PDB file
by Ashok Nayak 29 Jul '15

29 Jul '15

Dear Phenix BB, I wish to extract xyz coordinates of Calpha atoms from the PDB file of my interest. Is there a program in Phenix or CCP4 for the same? Suggestions are highly appreciated. Thanks in advance Ashok Nayak Grad Student GN Ramachandran Structural Biology Lab., MSB Div CSIR-CDRI Lucknow India

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weird problem with autosol
by Almudena Ponce Salvatierra 28 Jul '15

28 Jul '15

Dear all, I give autosol a list of HA sites generated with SHARP, an mtz file and the sequence of my protein and I get the following: "Invalid MTZ column_types for the given miller_array." DO you know if this is a bug? Or something else? my mtz contains all the relevant columns, so I don't understand why I get such a message. Thanks a lot in advance. Best, 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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Covalent Linker
by Courtney Daczkowski 27 Jul '15

27 Jul '15

We are currently trying to build a model that has a nonstandard ligand that is covalently bonded to two peptide chains. We've placed the ligand and linked it using Coot, but phenix.refine keeps removing the links. We generated the restraints using Elbow and wrote the .edits file using phenix.link_edits, but phenix.refine is still removing the links. We also tried turning on automatic ligand linking in phenix.refine, but that didn't work either. Any advice? Thanks. Courtney

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Parameters of a metal ion do not change during refinement
by Ezequiel Noguera 27 Jul '15

27 Jul '15

I added a Cu(II) ion in a blob of density using Coot (this metal is used in crystallization solution). When I refined using phenix, I noted that occupancy does not change from the arbitrary value that I set in Coot, and negative density remains when refinement is complete. When I manually adjust occupancy to 0.3, phenix changes it to 0.29, and no negative density is seen, however B-factor does not move from my arbitrary setting of 30 in Coot. I worry if something is wrong in my refinement strategy. I thank any suggestion.Some additional information: my mtz is merged F's, resolution is 1.3 A, refinement strategy includes XYZ coordinates, Occupancies and Individual B-factors. Ezequiel

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on refine related to b-factor
by Smith Liu 25 Jul '15

25 Jul '15

Suppose a 500-aa protein crystal structure has a flexible loop of 30 aas, and the loop fragment has a relatively high b-factor (above 100) in comparison with the whole protein b-factor. Is any refine strategy we can refine so that the b-factor of that loop fragment will be decreased? Smith

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Phenix Autobuild error
by Xiao Lei 25 Jul '15

25 Jul '15

Hi All, I am using Phenix autobuild (version 1.10pre on CentOS) and I failed with an error message (I put it below). My input experimental data (in MTZ format) is 2.5A, with space group C2, and 1 molecule per ASU (No NCS copies), the molecule contains two protein chains and one double-strand DNA (heterodimer protein bound to dsDNA). It seems to me the error is because in my model PDB there are different atoms in DNA with the same name. How can I fix this problem? Error message from phenix.refine: number of groups of duplicate atom labels: 4 total number of affected atoms: 8 group "HETATM 4930 O3' DT C 716 .*. O " "HETATM 5471 O3' DT C 716 .*. O " group "HETATM 4937 C7 DT C 716 .*. C " "HETATM 5472 C7 DT C 716 .*. C " group "HETATM 4950 O3' DG C 717 .*. O " "HETATM 5473 O3' DG C 717 .*. O " group "HETATM 4964 O6 DG C 717 .*. O " "HETATM 5474 O6 DG C 717 .*. O " Refinement failed... Thanks ahead. Xiao

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