- phenixbb - phenix-online.org

a small trick for SDS-Gel storage
by Kevin Jin 21 Mar '12

21 Mar '12

Dear All, Maybe most of you already knew. I just put my understanding of SDS page gel storage here, if you want to make gel yourself and safe some money. http://www.jinkai.org/SDS_page.html If I am wrong, please let me know. Sharing knowledge each other is always joyful. -- Kevin Jin Protein crystallographer and Biopolymer chemist Personal Website: http://www.jinkai.org/

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A possible conjugative relaxase with novel fold for DNA cleavage?
by Kevin Jin 20 Mar '12

20 Mar '12

Dear All, The protein structure of Jann_2411 (PDB 3H0N) from Jannaschia sp. strain CCS1 carries a novel fold for unknown function. Zn-finger is indentified in the C-terminus. However, the N-terminus with a metal binding site presents a novel fold. As the person who solved and characterized this protein, I would like to put some further observation here for your consideration. My analysis is available here: http://www.jinkai.org/Novel_fold_3H0N.html Best regards, Kevin -- Kevin Jin Protein crystallographer and Biopolymer chemist Personal Website: http://www.jinkai.org/

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NCS operators
by Melania Strycharska 20 Mar '12

20 Mar '12

Dear all, I have a bit of a problem applying NCS to my fairly low resolution structure. If I try to look for NCS symmetry automatically - phenix doesn't find any. If I specify sections that I want to be related by NCS, the script usually crashes. I have a dimer in the asymmetric unit, however it appears that one domain is related by 3-fold symmetry while the other is related by 6 fold symmetry. I can "cheat" phenix and generate operators for each of the domains by feeding a stripped pdb file (one that contains only a dimer of one domain or the other) to phenix.simple_ncs_from_pdb and then it easily identifies the ncs operators... unfortunately the simple_ncs_from_pdb.ncs file generated that is meant to be fed into phenix.refine contains only the chain selections, not the actual operators. Is there a way to specify different NCS operators (rotational matrix and translational vector) for specific chain selections in the .eff file or under GUI? or if there isn't, how can I still take advantage of my NCS symmetry? Also, is there any obvious reason why NCS operators that I generated with Phenix do not match the operators that I found using CCP4 Lsqkab? (yes I already accounted for chain A moving onto B or chain B moving onto A) Can I choose to apply NCS symmetry to just my backbone? How would I specify that? thanks so much! Melania

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GUI parameter files
by Leonid Sazanov 19 Mar '12

19 Mar '12

Hi, I have a following problem in dev-874 version: If I restore a previous job in refine GUI, to run it with modified settings, and include a new parameter file .eff with definitinon of secondary structure restrains, these new restrains are combined with previously used restrains. How do i get rid of previous restrains? Older file is not visible in inputs, but its settings are still used. And in general, how can one be sure which parameters are used at the start of each refine run? If older settings loaded from .eff or .param file are not visible, the only way is to look through new .eff file, which takes a lot of time. Has this been solved in latest builds perhaps? Thank you, Leo -- Dr. Leonid A. Sazanov Research group leader Medical Research Council Mitochondrial Biology Unit Wellcome Trust / MRC Building Hills Road Cambridge CB2 0XY WEB: www.mrc-mbu.cam.ac.uk Tel: +44-1223-252910 Fax: +44-1223-252915

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Refinement using data with pseudo translational symmetry
by Bret Wallace 18 Mar '12

18 Mar '12

To all, First I apologize for the long email, but I wont to make sure that I give enough information to describe the problem. I have been working on a structure of two proteins in complex with each other (one forms a homodimer, with each monomer bound to 1 monomer of the other protein), using data, that according to phenix.xtriage contains pseudo translational symmetry (output pasted below). I have done a lot of searching of both the phenixBB and ccp4BB regarding solutions to this problem, but unfortunately most responses seem to be directed at resolving issues with MR. I have successfully performed MR using both phenix phaser, ccp4 phaser (the most updated version), as well as molrep. The issue arises upon structure refinement, where my Rwork and Rfree are essentially stuck at 28 and 33, respectively. I have built the entire structure, including ligands, except for any solvent molecules. Here are the details for the data/structure: SG: P212121 Cell: 72 124 175 90 90 90 Res: 50-2.8 Patterson analyses ------------------ Largest Patterson peak with length larger than 15 Angstrom Frac. coord. : 0.155 0.000 0.500 Distance to origin : 87.222 Height (origin=100) : 34.517 p_value(height) : 6.739e-04 The reported p_value has the following meaning: The probability that a peak of the specified height or larger is found in a Patterson function of a macro molecule that does not have any translational pseudo symmetry is equal to 6.739e-04. p_values smaller than 0.05 might indicate weak translational pseudo symmetry, or the self vector of a large anomalous scatterer such as Hg, whereas values smaller than 1e-3 are a very strong indication for the presence of translational pseudo symmetry. Xtriage notes that the if the PTS is crystallographic, that C2221 is a possible SG (x+1/6, y, z+1/2). However, neither XDS or HKL picks orthorhombic C, and the indexing/integrating doesn't work if I force it. I should also not there is no twinning detected by either xtriage or twinning servers. I have done a number of things to try to resolve this: -rescaling in lower symmetry (P21 and P1) -rescaling in the PG P222 and letting the MR program decide the proper space group -shifting origin and re-refining -a number of different refinement protocols (TLS, optimized weights/adp, simulated annealing, several cycles of rigid body, etc.) I have used HKL2000 and XDS to index/integrate/scale the data, both yield the same results, with slightly different completeness and Rmerge values, but refining with either gives similar R factor values. Does any know of any other possible things I should try to refine this data? I am happy to provide additional information upon request. Thanks in advance for any help! Bret

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selectively remove bond length restraints on atoms
by Maxime Cuypers 15 Mar '12

15 Mar '12

hello, What is the best way to selectively remove bond length restraints on some selected atoms for phenix.refine? i found the commands for a .param file: refinement { geometry_restraints.remove { angles = None dihedrals = None chiralities = None planarities = None } } but no bond length command in the manual online. http://www.phenix-online.org/version_docs/dev-283/refinement.htm otherwise there is the commands refinement { geometry_restraints.edit { bond { action= *delete change atom_selection_1= (selection1 here) atom_selection_2= (selection2 here) distance_ideal= None } } } is it a good way to deal with the problem ? thanks in advance for your help. Maxime

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crystal packing pattern
by bsubedi＠btk.fi 15 Mar '12

15 Mar '12

Hi All, Could someone help me with a program/tool to see the pattern of protein packing in the crystal. I would like to make comparative study between regions of the protein in two different chains and if crystal packing has some effect on conformational alteration. Kind regards, World

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Reminder: BCA/CCP4 Summer School 2012
by Airlie McCoy 15 Mar '12

15 Mar '12

This is a reminder that applications are now open for the BCA/CCP4 Summer School in Protein Crystallography to be held at Diamond (UK) from Tuesday 28th August to Sunday 2nd September 2012. Applications close 1st May 2012. The course is suitable for PhD students in macromolecular crystallography who started in or before October 2011, and postdocs new to macromolecular crystallography. Please note that references from supervisors are also due by 1st May 2012, so don't leave your application until the last minute! For more information see: http://www.diamond.ac.uk/Home/Events/BCA-Summer-School-2012.html Application form: http://www.diamond.ac.uk/Home/Events/BCA-Summer-School-2012/Application-Pag…

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Transfer to new computer
by Colin Levy 15 Mar '12

15 Mar '12

Hi, Is it possible to transfer Phenix along with it's archive to a new computer? I have a fresh install of Phenix on the new machine and a copy of all the original files and folders from the old machine but cant figure how to point Phenix to the correct place. Thanks Colin

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March 15, 2012 deadline- User proposal submission for Collaborative Crystallography at BCSB
by Banumathi Sankaran 14 Mar '12

14 Mar '12

Dear Users, The deadline for May/June 2012 Collaborative Crystallography proposals will be *Mar 15, 2012. * ------------------------------------------------------------------------ Through the Collaborative Crystallography Program (CC) at the Advanced Light Source (ALS), scientists can send protein crystals to Berkeley Center for Structural Biology (BCSB) staff researchers for data collection and analysis. The CC Program can provide a number of benefits to researchers: * Obtain high quality data and analysis through collaborating with expert beamline researchers; * Rapid turn around on projects; and * Reduced travel costs. To apply, please submit a proposal through the ALS General User proposal review process for beamtime allocation. Proposals are reviewed and ranked by the Proposal Study Panel, and beamtime is allocated accordingly. BCSB staff schedule the CC projects on Beamlines 5.0.1 and 5.0.2 to fit into the available resources. Only non-proprietary projects will be accepted. As a condition of participation, BCSB staff researchers who participate in data collection and/or analysis must be appropriately acknowledged - typically being included as authors on publications and in PDB depositions. Please consult the website for additional information at: http://bcsb.als.lbl.gov/wiki/index.php/Collaborative_Crystallography ------------------------------------------------------------ ----------------------------- How To Apply: To learn more, go to: http://www.als.lbl.gov/als/quickguide/becomealsuser.html To submit a proposal, go to: http://alsusweb.lbl.gov/. Scroll down to "*Structural Biology beamlines (includes protein SAXS)*" and click on "New Proposal." Enter your proposal information, with attention to the following details: * For question 3/First choice, select "5.0.1 (Monochromatic);" for question 3/Second choice, select "5.0.2 (MAD)." * Check box (yes) in response to question (7) "Do you want collaborative crystallography (beamline 5.0.1 or 5.0.2 only) * In question 4, please describe a specific research project with a clear end point. In order to request CC time for May/June 2012 allocation period, proposals must be submitted by *March 15, 2012.* The deadline for CC proposals for the time period July/August 2012 will be May 15, 2012. Regards, Banumathi Sankaran

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David Sayre
by Paul Adams 12 Mar '12

12 Mar '12

On behalf of the Phenix development team: We regret deeply the passing of David Sayre on Feb. 23, 2012. David Sayre made profound contributions to crystallography and scientific computing that continue to have a major impact decades later. An obituary summarizing his many achievements was posted by Physics Today (http://www.physicstoday.org/1.2732466). In crystallography, Sayre’s fundamental insight into the implications of the atomic nature of crystal structures and the relationships between crystallographic structure factors allowed him to develop in 1952 the brilliantly simple Sayre equation relating each structure factor to all other structure factors. The Sayre equation has had a well-known yet greatly under-appreciated significance in small-molecule crystallography, both in its original form and in the equivalent probabilistic forms implemented later as part of direct methods. These methods have profoundly affected macromolecular crystallography in the last decade because of their astounding power for determination of heavy-atom substructures. The use of direct methods has made possible solution of the positions of as many as 160 selenium atoms in large macromolecular structures. To appreciate the feat that this represents, it is useful to consider that many macromolecular crystallographers were initially hesitant to use the seleno-methionine approach at all for structures that had more than about 10 selenium atoms for fear that the substructure could not be solved. Sayre’s recent work on phasing X-ray diffraction data from single large objects such as a yeast cell and single small objects such as a single protein molecule was groundbreaking in a different way. This work is revolutionary because of its boldness, and because of the elegantly simple approach to phase determination that Sayre developed. Once again Sayre took a fundamental real-space feature of the diffraction image and used it to obtain phase relationships. In this case the diffraction forms a continuous pattern from a single object, and the feature is the lack of contrast outside of the object. While the idea of using a mask of the object (the “support”) to define phases has been used for some time in many contexts, it was far from obvious that this could be done with a single cell or with a single protein molecule. Sayre and his colleagues systematically showed theoretically and then experimentally that each step in this process can be carried out and that the required signal can be extracted to obtain an X-ray image of microdots and later even a yeast cell. Others have followed up his ideas for phasing data from a single protein molecule. This work was of fundamental and transforming importance because few would have believed that the ideas were remotely feasible, and now they have a sound theoretical basis and experimental demonstrations, allowing anyone to think of new and powerful ways to use these approaches. The breadth of Sayre's intellectual spectrum reached far beyond crystallography. He was also a member of the IBM team that developed the original Fortran compiler, the first high-level programming tool (see http://www.ibm.com/ibm100/us/en/icons/fortran/team/ for more details). Currently, 55 years after the first commercial release of Fortran, this language is still in wide use. The history of crystallographic computing, and scientific computing in general, cannot be separated from the success of Fortran, made possible by the amazing IBM team that included Sayre. In spite of his great accomplishments, David Sayre was modest and approachable in person, and he was generous in sharing credit with his colleagues. He will be greatly missed. -- 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 64, Room 248 Tel: 1-510-486-4225, Fax: 1-510-486-5909 http://cci.lbl.gov/paul Lawrence Berkeley Laboratory 1 Cyclotron Road BLDG 64R0121 Berkeley, CA 94720, USA. Executive Assistant: Louise Benvenue [ LBenvenue(a)lbl.gov ][ 1-510-495-2506 ] --

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phenix.elbow problem
by Simon Kolstoe 12 Mar '12

12 Mar '12

Hi there, Who's the best person to talk to when phenix.elbow is not assigning correct geometry to a molecule? Thanks, Simon --------------------------------------------------------------- Dr Simon Kolstoe Laboratory for Protein Crystallography Wolfson Drug Discovery Unit University College London Rowland Hill Street, London NW3 2PF Tel: 020 7433 2765 http://www.ucl.ac.uk/~rmhasek ---------------------------------------------------------------

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error after adp refinement
by Christian Roth 10 Mar '12

10 Mar '12

Dear Phenix Team, I started a refinement with anisotropic adp and weight optimization and directly after the optimization step an error appeared which never appeared befor for me. The previous steps of mask optimization and xyz refinement worked well. Best Regards Christian AssertionError : Traceback: File "/userdata-2/christian/phenix- dev-979/cctbx_project/libtbx/thread_utils.py", line 229, in run return_value = self._target(self._args, self._kwargs, self._c) File "/userdata-2/christian/phenix- dev-979/cctbx_project/libtbx/runtime_utils.py", line 72, in __call__ result = self.target() File "/userdata-2/christian/phenix- dev-979/phenix/phenix/refinement/runtime.py", line 68, in __call__ call_back_handler=callback) File "/userdata-2/christian/phenix- dev-979/phenix/phenix/refinement/command_line.py", line 97, in run call_back_handler=call_back_handler) File "/userdata-2/christian/phenix- dev-979/phenix/phenix/refinement/driver.py", line 1494, in run ncs_manager = self.ncs_manager) File "/userdata-2/christian/phenix- dev-979/phenix/phenix/refinement/strategies.py", line 1046, in refinement_machine h_params = h_params) File "/userdata-2/christian/phenix- dev-979/cctbx_project/mmtbx/refinement/adp_refinement.py", line 212, in __init__ nproc = nproc) File "/userdata-2/christian/phenix- dev-979/cctbx_project/mmtbx/refinement/adp_refinement.py", line 389, in __init__ compute_gradients=False).target_work()) Platform info: __FILE__ = /net/longnose/scratch2/phenix/phenix- dev-979/cctbx_project/boost_adaptbx/meta_ext.cpp __DATE__ = Feb 7 2012 __TIME__ = 02:05:24 __i386__ __linux __GNUC__ = 3 __GNUC_MINOR__ = 4 __GNUC_PATCHLEVEL__ = 2 boost::python::cxxabi_cxa_demangle_is_broken(): false __GXX_WEAK__ = 1 __VERSION__ = 3.4.2 20041017 (Red Hat 3.4.2-6.fc3) FE_INEXACT = 32 FE_DIVBYZERO = 4 FE_UNDERFLOW = 16 FE_OVERFLOW = 8 FE_INVALID = 1 FE_ALL_EXCEPT = 61 BOOST_LIB_VERSION = 1_48 PY_VERSION = 2.7.2 PYTHON_API_VERSION = 1013 sizeof(bool) = 1 sizeof(short) = 2 sizeof(int) = 4 sizeof(long) = 4 sizeof(std::size_t) = 4 sizeof(void*) = 4 sizeof(long long) = 8 sizeof(float) = 4 sizeof(double) = 8 sizeof(long double) = 12 sizeof(boost::int32_t) = 4 sizeof(boost::uint32_t) = 4 sizeof(wchar_t) = 4 __PTRDIFF_TYPE__ Py_USING_UNICODE sizeof(PY_UNICODE_TYPE) = 2 gnu libc version: 2.10.1 BOOST_ADAPTBX_TYPE_ID_SIZE_T_EQ_UNSIGNED os.name: posix sys.platform: linux2 sys.byteorder: little platform.platform(): Linux-2.6.31-23-generic-pae-i686-with-debian-squeeze-sid platform.architecture(): ('32bit', 'ELF') floating_point_exceptions.division_by_zero_trapped: False floating_point_exceptions.invalid_trapped: False floating_point_exceptions.overflow_trapped: False number of processors: 8 Memory total: 25,405,636,608 Memory free: 20,305,633,280 import thread: OK "hello" = ['h', 'e', 'l', 'l', 'o'] u"hello" = ['h', '\x00', 'e', '\x00', 'l', '\x00', 'l', '\x00', 'o', '\x00'] u"\u00C5" = ['\xc5', '\x00'] as utf-8 = ['\xc3', '\x85'] LATIN CAPITAL LETTER A WITH RING ABOVE = Å

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Calculating Bijvoet difference Fourier map
by John Rose 08 Mar '12

08 Mar '12

Hi, I am some what new to PHENIX and using the Mac GUI. I want to compute a Bijvoet difference Fourier map. Any help would be appreciated. John Rose

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autobuild omit map as Fo-Fc
by Ursula Schulze-Gahmen 08 Mar '12

08 Mar '12

I calculated an omit-map for my model using the following command inpt: phenix.autobuild data=HKL2000+R.mtz model=ptefb_A4_refine_43.pdb omit_region_specification=omit_around_pdb omit_box_pdb_list=G_chain.pdb composite_omit_type=refine_omit maps_only=true I would like to display a 2Fo-Fc and Fo-Fc map but I cannot find the overall_best_refine_map_coeffs.mtz output file that should have these coefficients according to the manual. I only see the overall_best_denmod_map_coeffs.mtz file. Can somebody tell how to best get to an omit Fo-Fc or 2Fo-Fc map? Thanks Ursula -- Ursula Schulze-Gahmen, Ph.D. Assistant Researcher UC Berkeley, QB3 356 Stanley Hall #3220 Berkeley, CA 94720-3220

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bins in phenix.refine
by Jianghai Zhu 06 Mar '12

06 Mar '12

Hi, A colleague asked me a question if phenix.refine can use user-input resolution bins for R and Rfree calculation. I am not sure if such parameters exist. -- Jianghai

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where is the fo-fc omit map?
by Yu, Hongjun 06 Mar '12

06 Mar '12

hello, It is so good that phenix can caculate sa-omit map so easily. But I am new to this. When I finish caculating, I can only get acess to 2fo-fc map whe I use coot to open the file: resolve_composite_map.mtz . How can I open the fo-fc omit map? I notice this from phenix.autobuild manual page "Note 1: be sure to use the weights in both resolve_composite_map.mtz and omit_region.mtz". I don't understand this because the omit_regin.mtz seem to be the omit box I specify. Is this correlated with my problem? Any advice is appreciated. Thank you in advance! Sincerely, Hongjun

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phenix.get_cc_mtz_pdb but allow for atom selections.
by Francis E Reyes 06 Mar '12

06 Mar '12

It'd be wonderful to pass in an atom selection (say backbone, or ligand or what have you) into phenix.get_cc_mtz_pdb . Is this functionality available in some other phenix util? Thanks! F --------------------------------------------- Francis E. Reyes M.Sc. 215 UCB University of Colorado at Boulder

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Batch conversion
by Theresa H 06 Mar '12

06 Mar '12

Hi all How can I use ADXV to batch conversion of diffraction image to tiff format? Would like to put about 20 of them in Powerpoint slides. Thank you. Theresa

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fwd: Reminder: CCP4 summer school at APS, in USA
by Nathaniel Echols 02 Mar '12

02 Mar '12

FYI, Paul Adams and Tom Terwilliger will both be presenting at this workshop. ---------- Forwarded message ---------- From: "Sanishvili, Ruslan" <rsanishvili(a)anl.gov> To: "'phenixbb(a)phenix-online.org'" <phenixbb(a)phenix-online.org> Cc: Date: Fri, 2 Mar 2012 14:22:53 -0600 Subject: Reminder: CCP4 summer school at APS, in USA Dear Colleagues, This is a reminder that the deadline for applications for the 5th annual CCP4 Summer School “From data collection to structure refinement and beyond” is April 17, 2012. The school will take place from June 19 through June 26, 2012 at the Advanced Photon Source (APS) near Chicago. There is no registration fee for the school. The students will be responsible for their own travel and lodging expenses. These and other details (The program, the list of speakers, the application process, accommodations, site access, contacts etc) can be found at the workshop website at http://www.ccp4.ac.uk/schools/APS-2012/index.php The school will include data collection, processing, structure solution, model building, refinement, validation, automation of many steps etc. Participants are encouraged to bring their own crystals, raw data or processed data for hands-on problem solving under the guidance of software developers and other experts. Garib, Ronan and Nukri Ruslan Sanishvili (Nukri), Ph.D. GM/CA-CAT Biosciences Division, ANL 9700 S. Cass Ave. Argonne, IL 60439 Tel: (630)252-0665 Fax: (630)252-0667 rsanishvili(a)anl.gov ________________________________ From: Sanishvili, Ruslan Sent: Monday, December 19, 2011 11:39 AM To: 'phenixbb(a)phenix-online.org' Subject: Annual CCP4 summer school in USA, at APS, June 19-26 Dear Colleagues, We are pleased to announce the fifth annual CCP4 summer school at Advanced Photon Source (APS), Argonne National Laboratory (ANL). All details can be found at http://www.ccp4.ac.uk/schools/APS-2012/ Title: "CCP4 school: From data collection to structure refinement and beyond" Dates: June 19 to 26. Site: Advanced Photon Source, Argonne National Laboratory, Argonne, Illinois (Near Chicago), USA The school content: Data collection workshop the first two days: beamline training and data collection on GM/CA-CAT beamlines 23ID-B and 23ID-D. For data collection, only the participants' crystals will be used. Software workshop: The rest of the time after data collection will feature many modern crystallographic software packages taught by authors and other experts. It will be organized in three Sections – lectures, tutorials and hands-on trouble-shooting. There will be model data sets available for tutorials but data, provided by participants, will have higher priority for the hands-on sessions. Applicants: Graduate students, postdoctoral researchers and young scientists at the assistant professor level are encouraged to apply. Only 20 applicants will be selected for participation. Participants of the workshop are strongly encouraged to bring their own problem data sets or crystals so the problems can be addressed during data collection workshop and/or hands-on sessions. Application: Application deadline is April 17. The application form, the program, contact info and other details can be found at http://www.ccp4.ac.uk/schools/APS-2012/ Fees: There is no fee for the workshop. The students will be responsible for their transportation and lodging. The workshop organizers will arrange economical lodging at the Argonne Guest House. The workshop will also cover the expenses for all meals and refreshments. Garib, Ronan and Nukri Ruslan Sanishvili (Nukri), Ph.D. GM/CA-CAT Biosciences Division, ANL 9700 S. Cass Ave. Argonne, IL 60439 Tel: (630)252-0665 Fax: (630)252-0667 rsanishvili(a)anl.gov

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xtriage output
by wtempel 02 Mar '12

02 Mar '12

Hello, this question is about the summary of xtriage output. I submitted merged scalepack intensity in space group P3. From scaling, the apparent point group is P622. H-tests for all three applicable twin laws indicate twin ratios around 45%. Does this merely indicate underestimated symmetry? STDOUT ends with this nugget: <stdout> The results of the L-test indicate that the intensity statistics Show more centric character than is expected for acentric data. </stdout> My questions: 1. What if anything should I infer about twinning from this last sentence? 2. What other data defects could this sentence indicate? Many thanks, Wolfram Tempel

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DEN refinement under phenix
by Melania Strycharska 02 Mar '12

02 Mar '12

Hi All, I was wondering whether anybody has successfully run the DEN refinement under phenix yet. I am having some problems with my scripts stalling without any error messages. What sort of reference models do people use? The following issues I am not quite clear on: - if I don't have a reference model should I call on my current pdb where the script calls for a reference model? - is it ok to use a single domain as a reference model or is it not enough to get the whole protein refined? - is it possible to use more than one reference model; in a case where I had structures of each domain solved separately? - can a reference model be a different protein or does it have to have the same sequence? Thanks a lot!

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Rfree refuse to come down
by #HEW KAI LI KELLY# 02 Mar '12

02 Mar '12

HI, I have a few questions about a dataset that I am working on currently. So I ran Xtraige and it tells me that other than pseudoNCS, there is no other problems like twinning etc. And then I used autoMR and Phaser from Phenix to run molecular replacement with a the structure of the same protein (but that is with DNA bound). The TFZ is more than 9 after from both the runs. Autobuild managed to build the 4 molecules in my ASU (Rfactor/Rfree = 28/32 for a resolution of 2.4A). But because there are some clashes and outliers in the Ramachandran Plot etc, I started to manually refine them in coot. In addition, there is a loop that is unable to fit into the density, so I chopped about 10 residues off each molecule in the ASU. However, as I started to refine the model from AutoBuild, my Rfree begins to climb. So currently, I am at Rfactor/Rfree=27/36. I don't know if there is anything wrong with I had done. So many thanks in advance for your advices on this!! Warmest Regards, Kelly Hew Nanyang Technogical University School of Biological Sciences Division of Structural Biology & Biochemistry Address : #07-01, IMCB, 61 Biopolis Drive, Proteos, Singapore 138673 Telephone (O): +65 65869673 Telephone (HP): +65 98713553

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Fwd: Hi Res Model. Maybe its time to Include Hydrogens?
by Yuri 02 Mar '12

02 Mar '12

Sue: I am not sure they are being included... I have the option checked, but the R values and difference maps tell me otherwise Pavel: A bug? That would be consistent with the behavior I observe. Even when I enable refinement with hydrogens individual or riding, i see essentially no difference in maps or Rfree values. -- Yuri Pompeu

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Hi Res Model. Maybe its time to Include Hydrogens?
by Yuri 02 Mar '12

02 Mar '12

Dear users, I am refining a 400 aa protein with data out to 1.16 A (real data). I am almost finished with refinement. I have good geometry, complete model and ligands Rw 0.11 Rf 0.13. Difference maps seem to be asking for more. See attached screen shot.Both maps 2Fo-Fc (non-filled) and Fo-Fc are contoured at 3 sigma. How should I handle this? I have used hydrogens all along (riding). Thanks for your time -- Yuri Pompeu

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phenix.reciprocal_space_arrays question
by Michael Thompson 01 Mar '12

01 Mar '12

Hi All, I have a very simple question about phenix.reciprocal_space_arrays. I apologize if this is obvious, but I could not find any info in the documentation or the bb archives. I just want to make sure that I am actually doing what I think I am doing. If I provide phenix.reciprocal_space_arrays with an .mtz file containing Fobs and a .pdb file for which I would like to calculate Fmodel and PHImodel, will the resulting Fmodel (and Fcalc, Fmask, Fbulk, etc.) be scaled to the Fobs from the input .mtz? Thanks for the help! Mike T. -- Michael C. Thompson Graduate Student Biochemistry & Molecular Biology Division Department of Chemistry & Biochemistry University of California, Los Angeles miket(a)chem.ucla.edu

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BCA/CCP4 Summer School 2012
by Airlie McCoy 01 Mar '12

01 Mar '12

Applications are now open for the BCA/CCP4 Summer School in Protein Crystallography to be held at Diamond (UK) from Tuesday 28th August to Sunday 2nd September 2012. Applications close 1st May 2012. The BCA/CCP4 Protein Crystallography Summer School is intended for students and researchers new to crystallography. Its dual aims are to provide comprehensive training in crystallography and to promote best practise within the British crystallographic community. The lectures cover the gamut of techniques required for a structure solution, from protein expression through to structure validation. Intensively supervised computer tutorials enable students to relate the theory presented in the lectures to practice. Although CCP4 programs will primarily be used in these tutorials, the aim will be to approach crystallographic questions in a software-agnostic manner. There will also be a crystal manipulation and cooling workshop. (Note that the course is scheduled during Diamond synchrotron downtime, so there will not be active data collection at the Diamond beamlines.) For more information on eligibility, cost, and applications see: http://www.diamond.ac.uk/Home/Events/BCA-Summer-School-2012.html Application form: http://www.diamond.ac.uk/Home/Events/BCA-Summer-School-2012/Application-Pag…

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NCS-averaged and superposed maps
by Mullins, Elwood 29 Feb '12

29 Feb '12

Is it possible to both NCS-average and superpose maps? I can do one or the other easily enough from the command line (phenix.ncs_average) and the GUI (Superpose maps). Unfortunately, both programs require the input to be an mtz file but output ccp4-style maps. I don't see a way to do this sequentially. Is there some other method that would allow me to perform both operations? Thanks, Elwood =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-= Elwood A. Mullins Ph.D. Candidate Department of Chemistry Washington University in St. Louis Campus Box 1134 One Brookings Drive Saint Louis, MO 63130-4899 Email: elwood.mullins(a)wustl.edu Tel: (765) 496-6814 Fax: (765) 494-7897 =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=

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R-free flags
by 刘世恒 29 Feb '12

29 Feb '12

Hi, According to the phenix documentation, phenix.refine generates free R that are evenly distributed over the resolution, making sure that relatively thin resolution bins receive enough of reflections. The default behavior is to flag 5% of reflections up to a maximum of 2000. However,in some high-resolution structure, the percent for R-free test set which was generated by phenix.refine might be smaller than 1%， and it was a small percentage. Are there anticles related to the generation of R-free flag by phenix? Sincerely yours, Shiheng Liu

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adding solvents other than water
by Subhani Bandara 28 Feb '12

28 Feb '12

Hi all, How can I identify atoms like Na+, K+ in the map, from the positive density. Also can I add solvents like MPD and Tris buffer if any. Is there a specific way or do I have to run ligand fit. Is there any material I can read on this. Thanks in advance. Subhani

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Fixing ligand position in refine
by Christopher Wanty 28 Feb '12

28 Feb '12

Hi, I have a problem with a phosphate moving out of position during refinement. The complication is that there is an existing phosphate in the same location as the one I'm trying to place, but the existing one is part of a modified residue, and there is clearly density for the alternative conformation of the phosphate, but it is also clearly not still bound to the residue. How do I make sure that the phosphate does not move away from where it should be? Attached image show the phosphate more or less where I want it, and you should be able to see where the existing phosphate is attached to the residue. The large red density blob is where phenix.refine tried to put the phosphate last time. Kind regards, Chris ------------------------------------------------------- Dr. Christopher Wanty christopher.wanty(a)uwa.edu.au Research Associate Biomolecular, Biomedical and Chemical Sciences, Building M310 University of Western Australia 35 Stirling Highway Crawley 6009 Western Australia Australia

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MSE MET occupancy issue
by Ming 28 Feb '12

28 Feb '12

Hi all, I was trying to refine a protein with phenix.refine. I want to refine AMSE and BMET with occupancies 0.5 and 0.5. What I did is modifying the pdb file by copy the coordinates of MET to MSE, and change the names to be AMSE and BMET, modifying the occupancy to be 0.5 and 0.5 for each one. Everything else like the atom names have been taken care of too. I used the readyset to make sure the pdb file is good. But phenix.refine keeps giving me error saying "numbers of atoms with unknown nonbonded energy type symbols ". Anyone here can help me with this please? Thanks in advance,

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Phenix Error while running refinement
by Subhani Bandara 27 Feb '12

27 Feb '12

Hi everyone, I am getting following error while running phenix refinement for a protein cocrystalized with a metal chelator complex. What could be the problem. AssertionError : Traceback: File "/Applications/PHENIX-1.7.3-928/Contents/phenix-1.7.3-928/cctbx_project/libtbx/thread_utils.py", line 229, in run return_value = self._target(self._args, self._kwargs, self._c) File "/Applications/PHENIX-1.7.3-928/Contents/phenix-1.7.3-928/cctbx_project/libtbx/runtime_utils.py", line 72, in __call__ result = self.target() File "/Applications/PHENIX-1.7.3-928/Contents/phenix-1.7.3-928/phenix/phenix/refinement/runtime.py", line 67, in __call__ call_back_handler=callback) File "/Applications/PHENIX-1.7.3-928/Contents/phenix-1.7.3-928/phenix/phenix/refinement/command_line.py", line 97, in run call_back_handler=call_back_handler) File "/Applications/PHENIX-1.7.3-928/Contents/phenix-1.7.3-928/phenix/phenix/refinement/driver.py", line 1478, in run ncs_manager = self.ncs_manager) File "/Applications/PHENIX-1.7.3-928/Contents/phenix-1.7.3-928/phenix/phenix/refinement/strategies.py", line 344, in refinement_machine model.show_occupancy_statistics(text = "Occupancies statistics", out=log) File "/Applications/PHENIX-1.7.3-928/Contents/phenix-1.7.3-928/cctbx_project/mmtbx/model.py", line 868, in show_occupancy_statistics self.xray_structure.set_occupancies(value=0., selection = less_than_zero) File "/Applications/PHENIX-1.7.3-928/Contents/phenix-1.7.3-928/cctbx_project/cctbx/xray/structure.py", line 480, in set_occupancies assert selection.size() == s.size() Thanks Subhani

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mr problem and changed unit cell parameters
by intekhab alam 27 Feb '12

27 Feb '12

Hi all I have collected 2 datasets; one for the native proteins (2.3Å resolution) while other is for a protein-protein complex (3.5Å resolution). The unit cell parameters for the native are a=120, b=196, c=109, a=g=90, b=114, while for the complex data it is a=122, b=197, c=300, a=g=90, b=93. I have successfully got a MR solution and refined the native dataset with 3 monomers in the asymmetric unit. Analysis of the protein complex dataset shows 41% pseudo translation and so far there is no success in molecular replacement for this dataset. Can anyone please suggest me ways to solve this problem. i already have tried different templates like monomer, dimer, trimer, tetramer etc with truncations of loop region. i am using phaser, autoMR, molrep. Regards -- INTEKHAB ALAM LABORATORY OF STRUCTURAL BIOINFORMATICS KOREA UNIVERSITY, SEOUL

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Using a parameter file in GUI
by Subhani Bandara 24 Feb '12

24 Feb '12

Hi everyone, I need to input a parameter file describing the bond lengths of a metal chelator complex in my protein. I used a text file containing the commands with .params extension. when I add this file in GUI inputs in refinement, it gives a message "Phenix did not recognize the file type". What is the file type I should use? The file contained commands similar to the following with my metal and ligand atom names. refinement.geometry_restraints.edits { zn_selection = chain X and resname ZN and resid 200 and name ZN his117_selection = chain X and resname HIS and resid 117 and name NE2 asp130_selection = chain X and resname ASP and resid 130 and name OD1 bond { action = *add atom_selection_1 = $zn_selection atom_selection_2 = $his117_selection symmetry_operation = None distance_ideal = 2.1 sigma = 0.02 slack = None } bond { action = *add atom_selection_1 = $zn_selection atom_selection_2 = $asp130_selection symmetry_operation = None distance_ideal = 2.1 sigma = 0.02 slack = None } } Then I used command line to run "phenix.refine model.pdb data.mtz elbow.cif restraints_edits.params" it again gave error saying .params is an unknown file type. Am I doing anything wrong and is there any other way to fix the distances of the metal chelator complex. Thanks Subhani

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importing projects problem
by Haytham Wahba 24 Feb '12

24 Feb '12

i moved my project from computer to another i did import project under Files. i got my projects with all jop history but when i try to restor jop i get this report (see below) after that i see only .eff file under the input file, No .Sca or the pdb i used before. even the result of refinment is not there and refinment setting which i did not use. i tried to change the path in .eff file to the new location for .sca and .pdb but i did not help could you help me in that. thank you Haytham (((ImportError : No module named f_model_info Traceback (most recent call last): File "/usr/local/phenix-1.7-650/phenix/wxGUI2/Home/Jobs.py", line 327, in OnDoubleClick self.list_frame.restore_job(job) File "/usr/local/phenix-1.7-650/phenix/wxGUI2/Home/Jobs.py", line 241, in restore_job app.restore_job(self.project.get_id(), current_job) File "/usr/local/phenix-1.7-650/phenix/wxGUI2/App.py", line 544, in restore_job use_template_gui=use_template_gui) File "/usr/local/phenix-1.7-650/phenix/wxGUI2/App.py", line 501, in restore_session frame.restore_session(output_dir, config_file, result) File "/usr/local/phenix-1.7-650/phenix/wxGUI2/Programs/Refine/Main.py", line 473, in restore_session (result, last_status_file) = self._load_result_files(output_dir) File "/usr/local/phenix-1.7-650/phenix/wxGUI2/Programs/Refine/Main.py", line 467, in _load_result_files refine_result = easy_pickle.load(result_file) File "/usr/local/phenix-1.7-650/cctbx_project/libtbx/easy_pickle.py", line 21, in load return cPickle.loads(_open(file_name, "rb").read()) ImportError: No module named f_model_info)))

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question about phenix rosetta with two chains
by Elena Seiradake 23 Feb '12

23 Feb '12

Dear Phenixians, I would like to use mr_rosetta to re-build a model with two copies per AU. Although the two copies have the same sequence, they adopt different conformations and one is partially disordered. So I don't want to impose NCS. Could someone please send me an example input file for running mr_rosetta with phenix for multiple chains of the same protein? I think this probably would have to contain "fragment_files_chain_list" and "fragment_files_3_mer_by_chain" etc. (?) I have tried including the above keys in my script, in various ways, but I always get the error: "Sorry, the file path/test_1.pdb representing group 1 has no atoms? This could indicate a problem with sequence alignment in rebuilding" When I run it with just one of the two chains in my pdb (using simple "fragment_file ="), it rebuilds happily. Also, when use both chains and impose NCS=2 it works, but then one of the two chains is forced into the wrong conformation. Any advice on how to change my script would be welcome! Below is part of my simple script, the one that runs ok, using "fragment_file =". seq_file= Seq.dat \ data=test.mtz \ search_models=test.pdb \ already_placed=True \ fragment_files= frag_A_3.gz \ fragment_files= frag_A_9.gz \ rescore_mr.relax=False \ rosetta_models=20 \ ncs_copies= 1\ Cheers Elena

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composite omit map
by Ursula Schulze-Gahmen 22 Feb '12

22 Feb '12

I tried to calculate a composite omit map in autobuild for 3 complexes in the au. The calculation finished without any problems, but the maps look not right. There is density for the molecule, but there is a lot of density in the solvent areas, which I never saw when I calculated regular 2fo-fc maps or fo-fc maps. I also have calculated omit maps in autobuild before for single problem region and never saw anything like this. Any idea what could have gone wrong? Where should I start looking? Ursula -- Ursula Schulze-Gahmen, Ph.D. Assistant Researcher UC Berkeley, QB3 356 Stanley Hall #3220 Berkeley, CA 94720-3220

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autoMR fixed ensemble error
by Alexander Batyuk 22 Feb '12

22 Feb '12

Dear all, I have the following error while trying to put fixed ensemble into AutoMR: Adding Ensemble c1 as fixed solution with: Euler angles: [359.98, 0.0, 0.0] Coords (orthogonal A): [-1.0, 0.476, -1.001] *************ERROR ENDING ******************* **************************************** AutoMR Input failed Python argument types in SOLU.addSOLU_6DIM_ENSE(InputMR_AUTO, str, list, bool, list, float, bool, bool, bool) did not match C++ signature: addSOLU_6DIM_ENSE(phaser::SOLU {lvalue}, std::string, scitbx::vec3<double>, bool, scitbx::vec3<double>, double, bool, bool, bool, bool, scitbx::vec3<double>, double) **************************************** *************ERROR ENDING ******************* What could be the reason for that? I'm running dev-986 on OS X 10.6.8. Stable 1.7.3 gives the same error. Best wishes, Alex -- Alex Batyuk The Plueckthun Lab www.bioc.uzh.ch/plueckthun

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Re: [phenixbb] CCN Jan 2012 article : find_alt_origin_sym_mate
by R.D. Oeffner 22 Feb '12

22 Feb '12

Dear Bryan, The factor 0.9 is a purely empirical term. It serves two functions. One is to soften the minimas when atoms coalesce and to also prevent taking the logarithm of a negative number. The closer it gets to zero the more accurately it pinpoints the global minimum when the MLAD score is used for identifying the best superposition betweent two molecules. But if it becomes two small chances are that the landscape of MLAD values will be dotted with many very deep local minima which might lead to wrong results. The square boxes under the min, max symbols are typos to be ignored, sorry. There are currently no plans to publish further details about find_alt_origin_sym_mate. Regards, Robert Oeffner On Wed, Feb 15, 2012 at 4:33 PM, Bryan Lepore <bryanlepore at gmail.com> wrote: > will the find_alt_origin_sym_mate article in CCN Jan. 2012 be > described in any other publications? ... e.g. Acta Cryst., because I am interested in particular : 1. what is the significance of the factor of 0.9 2. is the MLAD a novel formula also, the 'min' and 'max' on p. 6 have small boxes under them [*] as if missing a character - are these integrals? -Bryan [*] tried evince and Adobe Reader on Linux, Adobe Acrobat on OSX 10.5.8 -- Robert Oeffner, Ph.D. Research Associate Department of Haematology, University of Cambridge Cambridge Institute of Medical Research Wellcome Trust / MRC Building, Hills Road, Cambridge, CB2 0XY www-structmed.cimr.cam.ac.uk, tel:01223763234, mobile:07712 887162

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error in running autobuild
by intekhab alam 21 Feb '12

21 Feb '12

hi i am working with phenix version 1.7.1-743. after running auto mr i tried to run autobuild but it failed and generated the following message. i am unable to run autobuild now. kindly help. OError : [Errno 5] Input/output error Traceback (most recent call last): File "/usr/local/phenix-1.7.1-743/phenix/wxGUI2/Runtime.py", line 172, in OnUpdate self.propagate_event(event, "OnUpdate") File "/usr/local/phenix-1.7.1-743/phenix/wxGUI2/Runtime.py", line 228, in propagate_event fn(event) File "/usr/local/phenix-1.7.1-743/phenix/wxGUI2/Programs/Phaser/Output.py", line 194, in OnUpdate self.process_callback(callback.message, callback.data) File "/usr/local/phenix-1.7.1-743/phenix/wxGUI2/Programs/Phaser/Output.py", line 209, in process_callback print "CALLBACK: %s %s" % (str(message), str(data)) IOError: [Errno 5] Input/output erro -- INTEKHAB ALAM LABORATORY OF STRUCTURAL BIOINFORMATICS KOREA UNIVERSITY, SEOUL

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FFT map coefficients only for certain chains
by Zhang yu 20 Feb '12

20 Feb '12

Dear Phenixers, Is that possible to generate map coefficients only for certain chains? For example, I have two chains, A and B, and I would like to output a map file only contains coefficients for chain A. The "isomesh" command in Pymol could generate similar images. But my purpose is not for presentation, I need a map file only contains coefficient for certain chains. In the interface of "FFT" tool in Phenix or CCP4, there is an option to include a PDB file and define atom selections. It describe that "If a PDB is supplied, the output map will cover the model plus a buffer on all sides. The atom selection parameters can be used to specify a smaller region" . If I define the selection as chain A when I run the FFT, the output map still covers a rectangular block containing chain A, instead of regions only surrounding chain A. Thanks. Yu Zhang

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CCN Jan 2012 article : find_alt_origin_sym_mate
by Bryan Lepore 17 Feb '12

17 Feb '12

will the find_alt_origin_sym_mate article in CCN Jan. 2012 be described in any other publications? -Bryan

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MRage
by Graeme Winter 17 Feb '12

17 Feb '12

Hi Folks, Following from the newsletter article I am trying to test out phaser.MRage. I have a well solved case which I know is in the pdb and a sequence file: phaser.MRage hklin=data.mtz composition.component.sequence=sequence.pir symmetry_exploration=pointgroup mode=full search.services=ncbi composition.count=3 however it generates a second component then complains it knows nothing about this: Sorry: Molecular weight needed for component 2. Any suggestions how to get around this? Many thanks, Graeme [gw56@ws050 rage]$ phaser.MRage hklin=data.mtz composition.component.sequence=sequence.pir symmetry_exploration=pointgroup mode=full search.services=ncbi composition.count=3 ############################################################################### # MRage version 0.1.0 # ############################################################################### All configuration options: -------------------------- hklin = data.mtz labin = None resolution_cutoff = 2.5 crystal_symmetry { unit_cell = None space_group = None } mode = quick *full symmetry_exploration = *pointgroup enantiomorph dataset output { root = "mrage" max_solutions_to_write = 0 gui_base_dir = None save_aniso_data = False job_title = None } composition { count = 3 component { sequence = sequence.pir stoichiometry = 1 ensemble { coordinates { pdb = None identity = None } } model_collection { trim = False coordinates { pdb = None identity = None } } template { pdb = None alignment = None } homology { file_name = None max_hits = 3 } search { services = local ncbi max_hits = 3 } } component { sequence = None stoichiometry = 1 ensemble { coordinates { pdb = None identity = None } } model_collection { trim = False coordinates { pdb = None identity = None } } template { pdb = None alignment = None } homology { file_name = None max_hits = 3 } search { services = local *ncbi max_hits = 3 } } } queue { technology = lsf threading sge *multiprocessing pbs cpus = 1 submission_command = None qslot_cpus = 1 } packing_pool = 20 rotation_peaks_cutoff = 0.75 post_refinement_cutoff = 0.75 final_selection_cutoff = 0.75 b_factor_refinement = True significant_peak_threshold = 7.0 sculptor_protocols = 11 10 13 12 1 3 2 5 4 7 6 9 8 *all minimal template_equivalence = False exclude_pdb_ids = None simple_run { enable = False component_sequence = None template_model = None blast_services = local ncbi max_blast_hits = 3 } Sorry: Molecular weight needed for component 2.

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AutoSol with 4.2A dataset for a protein/DNA complex
by Wei Shi 17 Feb '12

17 Feb '12

Hi everyone, I have got a 4.2A SeMet MAD dataset for a protein-DNA complex. And, the native dataset for this protein-DNA complex is ~3.2A. The space group for the native and SeMet crystals seem to be different. I am not sure whether it’s possible to solve the structure with the current data I have, and wondering whether any of you have experience with working with this low-resolution data and any suggestion for me. I processed the data with XDS in space group P31, and used *.cns.hkl file from XDSCONV as an input for AutoSol and also include the sequence for protein only. The protein dimer has 418 residues and DNA is 32bp. I run Autosol with the default setting. Below is statistics I got. It seems that I didn’t get anything promising. Any comment or suggestion about what to try next? Thank you so much! Statistics: Top solution: 2 Sites: 11. Space group: P32. FOM: 0.550. BAYES-CC: 8.10. Residues: 465 Side-chains: 0. Chains: 60. Model CC: 0.67 R-work: 0.4100 R-free: 0.4569. Under Heavy-atom search and phasing: Space group # of refined sites FOM Overall score R-factor Map skew Corr. of local RMS density Solution1 P31 11 0.530 8.10+/-11.80 0.4184 -0.12 0.66 Solution2 P32 11 0.550 8.10+/-11.80 0.3881 -0.10 0.66 Best, Wei

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Comprehension of Orotidine 5'-Monophosphate Decarboxylase
by Kevin Jin 16 Feb '12

16 Feb '12

Dear all, I wrote a story for Orotidine 5'-Monophosphate Decarboxylase. http://www.jinkai.org/Enzymology.html Best, Kevin

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Re: [phenixbb] qFit error in fixing alternate conformations
by Subhani Bandara 15 Feb '12

15 Feb '12

Hi, I used qFIT to fix the alternative conformations of my protein with a chelator complex, by submitting a PDB file and a mtz file. But it gave following error. What could be the reason for this. > > ___Run time error messages (if any):___ > xyz.pdb mtz.rfl FP SIGFP > Sorry: No matching array: refinement.input.xray_data.labels=FP,SIGFP > Thanks Subhani

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Re: [phenixbb] Example datasets
by mohamed noor 15 Feb '12

15 Feb '12

Dear Phenix users Is there some examples datasets involving 3-wavelength MAD phasing available? I would like to learn from indexing to structure solution with a combination of CCP4 and Phenix if possible. Thanks.

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cbf file
by Theresa H 15 Feb '12

15 Feb '12

Hi all Is there a utility to convert cbf file from Pilatus detector to mtz in Phenix? Thank you. Theresa

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Re: [phenixbb] alternative conformation of residues
by Subhani Bandara 15 Feb '12

15 Feb '12

Hi all, I have a protein where three consecutive amino acids have alternative conformations. I edited the PDB file to have those altloc and made total occupancy of A and B to 1.00. But after refinement both A and B are overlapping and I could see the positive density for one conformation away from that (may be b'se I didn't change coordinates of B conformation). How can I move the B altloc in to the positive density. Do I have to edit the coordinates on PDB and if so how can Ido that? Thanks in advance for any help Subhani

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