- phenixbb - phenix-online.org

how to avoid self disulfide bond in phenix refinement?
by Chen Chen 14 Apr '08

14 Apr '08

Hi, I am having a problem in phenix.refine. I ran phenix.refine --dry_run foo.mtz foo.pdb The program generate a parameter file named foo.param. I made some modification of foo.param. Then ran phenix.refine foo.mtz foo.pdb foo.param The program reports a weir error message: ========================== Set up restraints manager ========================== Number of disulfides: simple=3, symmetry=0 Simple disulfide: " SG CYS A 29 " segID="A " - " SG CYS A 29 " segID="A " distance=0.00 Simple disulfide: " SG CYS A 180 " segID="A " - " SG CYS A 180 " segID="A " distance=0.00 Simple disulfide: " SG CYS A 286 " segID="A " - " SG CYS A 286 " segID="A " distance=0.00 ... Sorry: Bond restraint model distance < 0.001: Please inspect the output above and correct the input PDB file. ======================================================================== It seems that the program recognized three "self-disulfide" bonds. This problem happens even I do not make any modification in foo.param. However, if I just ran phenix.refine foo.mtz foo.pdb with every parameter at default, the programs runs OK without the above error. I am wondering if it is a bug or if I made some mistakes. Thanks Chen -- Chen Chen, Ph. D., Research Associate Center for Advanced Research in Biotechnology (CARB), University of Maryland Biotechnology Institute (UMBI), 9600 Gudelsky Drive, Rockville, MD 20850 Office Phone: 240-314-6122

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Searchable phenixbb
by Mark Collins 11 Apr '08

11 Apr '08

Hi phenix community Is there a search function for this bb, as there is for the ccp4bb? I have some questions about twinning, TLS and alternate conformations in phenix.refine. I hate repeating questions that have been answered previously but going thru the Archives month by month is proving to be a little slow. Thanks Mark Collins

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Persistence of CONECT records?
by Warren DeLano 10 Apr '08

10 Apr '08

Though I wouldn't mind PyMOL taking credit for CONECT valence encoding, this was in fact a convention originally employed by MacroModel which I adopted from Schrodinger. According to OpenBabel maintainer Geoff Hutchinson, it is also a convention supported by the OpenBabel chemical interchange software, and it according to OpenEye's docs, OEChem supports it as well (with the OEPDBFlag::ORDERS, BONDS, and BOTH flags to OEWritePDBFile). Given that four popular tools already support this convention, shouldn't PHENIX do so as well? ________________________________ Message: 4 Date: Thu, 10 Apr 2008 12:53:27 -0400 From: "Schubert, Carsten [PRDUS]" <CSCHUBER(a)prdus.jnj.com> Subject: [phenixbb] Persistence of CONNECT records? To: <phenixbb(a)phenix-online.org> Message-ID: <889E20E3723D0C45A493DA5DA87D854E01E876B6(a)JNJUSRAGMS02.na.jnj.com> Content-Type: text/plain; charset="iso-8859-1" Hi, I noticed that the CONNECT records of ligands generated in elbow get deleted in phenix.refine. Even specifing both the protein and ligand file (with CONNECT records) in the .def files, does not retain these records. For us they are coming in handy since they specify the bond order of the ligands. This is important for display in PyMol, which assigns bond orders based on these records. Would it be possible to keep the CONNECT records in the output file of phenix.refine? Obviously the numbering would need to be adjusted and I have not yet checked if some of the model building programs like coot would be able to handle this situation correctly. Cheers, Carsten

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Persistence of CONNECT records?
by Schubert, Carsten [PRDUS] 10 Apr '08

10 Apr '08

Hi, I noticed that the CONNECT records of ligands generated in elbow get deleted in phenix.refine. Even specifing both the protein and ligand file (with CONNECT records) in the .def files, does not retain these records. For us they are coming in handy since they specify the bond order of the ligands. This is important for display in PyMol, which assigns bond orders based on these records. Would it be possible to keep the CONNECT records in the output file of phenix.refine? Obviously the numbering would need to be adjusted and I have not yet checked if some of the model building programs like coot would be able to handle this situation correctly. Cheers, Carsten

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Ignoring SegIDs
by Stephen Graham 10 Apr '08

10 Apr '08

Hi all, Apologies if this is a dumb question, but... Is there a way to get phenix.refine to ignore segids? I ask because COOT seems to be blithely unaware of segids and they have a habit of disappearing when one is rebuilding a model, resulting in very odd geometries when the side chain of a residue is in segment ' ' and the main chain is in segment 'A'. Alternatively, is there a 'convert chain IDs to segids' option like in CNS? Basically, I would like the segids removed/fixed/ignored automagically at the start of refinement (since I never use them for anything useful anyway). Thanks, Stephen -- Dr Stephen Graham Nuffield Medical Fellow Division of Structural Biology Wellcome Trust Centre for Human Genetics Roosevelt Drive Oxford OX3 7BN United Kingdom Phone: +44 1865 287 549

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phenix-cns conversion
by Sean Johnson 08 Apr '08

08 Apr '08

What is the best way to convert phases obtained from phenix to a usable cns format? I have 3.6 A maps that were SAD phased and density modified using phenix. I now want to use some of the cns refinement options - like torsion angle refinement. I tried converting structure factors and HL coefficients to cns format using phenix.reflection_file_converter, but when I run cns input files, I start getting errors like the ones shown below (this is from density_modify.inp): _____ Program version= 1.2 File version= 1.2 %XMAPASU-AUTOmem: increasing memory allocation to 2000000 Minimum brick that covers asymmetric unit: A= 0,..., 150 B= 0,..., 150 C= 0,..., 36 Sum of 21042 elements = 21042.0000 SHOW: average of 810150 elements= 0.0000 ANOMalous=FALSe {OFF} XMPST: average = 0.0000 minimum = 0.0000 maximum = 0.0000 XMPST: r.m.s. = 0.0000 norm = 0.0000 XMHISTO: (default from map) RHOMIN and RHOMAX = 0.0000 0.0000 %XMHISTO-ERR: a complete flat map. XMHISTO: (default from map) SLOT width = 0.000000 %XMHISTO-ERR: the SLOT width is too small 0.00000 XMHISTO: the number of slots MBINS=10000 and width SLOT= 0.0000 %XDOTYPE-ERR: Variable/type mismatch: do (masksol=1) (real(automap) <= $cutoff) ^ %DO-ERR: Data type mismatch. Selection must be a logical expression.: do (masksol=1) (real(automap) <= $cutoff) ^ %SHOW error encountered: There were errors in DO expression. (CNS is in mode: SET ABORT=NORMal END) ***************************************************** ABORT mode will terminate program execution. ***************************************************** Program will stop immediately. ______ I'm guessing that the problem has to do with the way I am converting the data to cns (since I have beautiful maps from phenix), but I'm really stuck right now. Any guidance would be appreciated. Thanks, Sean Johnson -- Sean Johnson, PhD R. Gaurth Hansen Assistant Professor Utah State University Department of Chemistry and Biochemistry 0300 Old Main Hill Logan, UT 84322-0300 (435) 797-2089 (435) 797-3390 (fax) sean.johnson(a)usu.edu

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ICSG 2008 Oxford Sept. 20-24, 2008
by Tom Terwilliger 07 Apr '08

07 Apr '08

Dear PHENIX users, I would like to encourage you to attend the 5th International Conference on Structural Genomics Sept 20-24th! This is the principal conference on structural genomics; it occurs every 2 years in a different part of the world. This year's meeting is in Oxford, UK and will have a lot of methods talks in addition to structural biology results. You can register at http://www.spine2.eu/ISGO . I'll look forward to seeing you in Oxford in September! All the best, Tom T The 5th International Conference on Structural Genomics (ICSG 2008) will be held in Oxford, UK on September 20-24th. The biennial Conference is the premier meeting for the Structural Genomics scientific community world-wide and is hosted on behalf of the International Structural Genomics Organization (ISGO) by Professor David Stuart at the University of Oxford, Division of Structural Biology. The Scientific Program will contain main scientific sessions, poster sessions, breakout discussion groups for specific topics and a social program and we expect to attract a worldwide audience of 500 delegates. Provisional Session Topics - Structural genomics, systems biology and complexes - The impact of structural genomics on treating diseases - Maximising impact on and integration with biology - HTP methods for membrane proteins - Hybrid/multidisciplinary approaches - Strategies for intrinsically unfolded proteins - Should we expand the protein universe or concentrate on biology? - New technologies The venue will be in the UK at the University of Oxford Examination Schools, High Street, Oxford. The Schools are in the heart of Oxford, central to all colleges, the main Oxford cultural and shopping areas and close to hotel and college accommodation. Registration and abstract submission is now available. Early registration and abstract submission deadline: 31st July 2008 http://www.spine2.eu/ISGO Social program reservations closing date: August 31st Thomas C. Terwilliger Mail Stop M888 Los Alamos National Laboratory Los Alamos, NM 87545 Tel: 505-667-0072 email: terwilliger(a)LANL.gov Fax: 505-665-3024 SOLVE web site: http://solve.lanl.gov PHENIX web site: http:www.phenix-online.org ISFI Integrated Center for Structure and Function Innovation web site: http://techcenter.mbi.ucla.edu TB Structural Genomics Consortium web site: http://www.doe-mbi.ucla.edu/TB

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"unlimit" command with Phenix GUI -unlimit: descriptors: Can't remove limit (Invalid argument)
by hari jayaram 03 Apr '08

03 Apr '08

Hi I am giving new to Phenix and the Phenix GUI. For starters I am trying to run the prime and switch strategy in Phenix. I know all my inputs are fine (see below) but the program aborts ( GUI turns red ) after a few seconds. I checked the resolve.com file in the directory and it has a command "unlimit" which in Leopard causes the following output to be echoed to the stdout "unlimit: descriptors: Can't remove limit (Invalid argument)" Once I deleted the unlimit command I can run the script just fine from a shell. My question is how can I tweak the Phenix GUI so that I dont have to run everything from the shell by manually editing the resolve.com file. The script that stops the GUI is reproduced here. Thanks for your help Hari Jayaram Postdoc , Brandeis University script: #!/bin/csh setenv SOLVEDIR /usr/local/phenix-1.3b-rc6/solve_resolve/ext_ref_files setenv SOLVEBIN /usr/local/phenix-1.3b-rc6/build/mac-intel-osx/solve_resolve/exe # setenv CCP4_OPEN UNKNOWN setenv SYMOP $SOLVEDIR/symop.lib unlimit # $SOLVEBIN/resolve<<EOF access_file mirima.dat labin FP=F_s3-3 FC=FC PHIC=PHIC FOM=FOM FWT=FWT hklin resolve_input.mtz mask_cycles 5 minor_cycles 10 hklout testpms-resolve.mtz no_build prime_and_switch EOF unlimit returns------------> [mango:hj/s3-3/prime_switch] hari% unlimit unlimit: descriptors: Can't remove limit (Invalid argument)

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Crystallographic Postdoctoral Research Position - Berkeley, USA
by Paul Adams 01 Apr '08

01 Apr '08

A postdoctoral research position is available immediately to work on challenging problems in structural biology: Postdoctoral Researcher Job ID: 21615 Division: Physical Biosciences Date Opened: 3/28/2008 This postdoctoral position will study the structure and function of macromolecular complexes and enzymes using X-ray crystallographic methods. This position will be joint between the Center for Protein Folding Machinery (proteinfoldingcenter.org) and the Joint BioEnergy Institute (www.jbei.org). The biological systems to be studied will include: Type-II chaperonins responsible for the refolding of unfolded proteins in archeal and mammalian cells, Glycosyl transferases responsible for the synthesis of hemicellulose in plants, and Novel glycosyl hydrolases that are able to breakdown cellulosic material for biofuels production. The candidate will have experience with using crystallographic methods to study macromolecules; robotic hardware for performing crystallization trials and imaging trays are available. Crystals will be characterized and data collected using the beamline resources of the Berkeley Center for Structural Biology at the Advanced Light Source. Essential: Primary duties and responsibilities will include using robotic hardware to perform screens for crystallization conditions. Optimization of crystallization conditions. Biophysical characterization of protein samples using standard techniques, such as dynamic light scattering. Characterization of crystals using the Berkeley Center for Structural Biology beamlines at the Advanced Light Source. Collection and analysis of diffraction data, model building and structure refinement. Extensive email and verbal interaction with other researchers. Marginal: Use of small angle X-ray scattering methods to analyze macromolecular complexes in solution. Essential: Ph.D. or equivalent in a scientific discipline, preferably structural biology, biology, or chemistry. Demonstrated experience of scientific research using crystallographic methods. Experience with crystallization methods. Solid interpersonal skills and the ability to work in a team environment are critical. Ability to communicate with a broad range of researchers. Marginal: Experience with the use of small angle scattering methods. Familiarity with robotic hardware for crystal growth. NOTE: This is a one year Term appointment with the possibility of renewal under the same terms and conditions, contingent upon continued funding and availability of work. Lawrence Berkeley National Laboratory is a world leader in science and engineering research, with 11 Nobel Prize recipients over the past 75 years, and 59 present members of the National Academy of Sciences. LBNL conducts unclassified research across a wide range of scientific disciplines and hosts four national user facilities. AA/ EEO employer committed to the development of a safe and diverse workforce. Learn more at http://www.lbl.gov. For more information about the Center for Protein Folding Machinery visit: http://proteinfoldingcenter.org/ and the Joint BioEnergy Institute visit: http://www.jbei.org/. For more information about the Berkeley Center for Structural Biology visit: http://bcsb.lbl.gov/ To apply: visit http://cjo.lbl.gov/ and search for the job number 21615. Please see http://cjo.lbl.gov/app_instr.html for details of how to apply. -- Paul Adams Deputy Division Director, Physical Biosciences Division, Lawrence Berkeley Lab Adjunct Professor, Department of Bioengineering, U.C. Berkeley Vice President for Technology, the Joint BioEnergy Institute Head, Berkeley Center for Structural Biology Building 64, Room 248 Tel: 510-486-4225, Fax: 510-486-5909 http://cci.lbl.gov/paul Lawrence Berkeley Laboratory 1 Cyclotron Road BLDG 64R0121 Berkeley, CA 94720, USA. --

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TLS, B factors, phenix and refmac
by Mischa Machius 01 Apr '08

01 Apr '08

Hi - Prompted by the recent discussions on B values, TLS refinement and differences between Phenix and refmac, we looked into these matters in more detail. We found that the crux of the problem lies in the fact that TLS and B value refinements are usually decoupled. We have developed a formalism that rolls both TLS and B value refinement into one. Phenix and refmac were modified to carry out the calculations, and the outputs from both programs were made compatible to allow proper comparison of the results. We found that the stability of the refinements is now vastly improved. More importantly, however, due to the reduced number of parameters, these calculations can be carried out to resolutions of 7 Å with meaningful representations of indiviual, anisotropic atomic displacement parameters. This low-resolution limit required reformulating the calculation of Wilson B values, but that is only a minor aspect of our treatment that can be neglected. The new, combined procedure for the simultaneous refinement of TLS/B is called 'TBS' refinement, reflecting all required components: Translation, Bibation, Screw. Interestingly, the ‘T’ component is fairly insensitive to input parameters, whereas the overall quality of the refinement is greatly dependent on the ‘B’ component. The more emphasis is put on ‘B’, the more convincing the results. There is a limit, though. At very high levels of ‘B’, the so-called ‘bibacity limit’, the refinement becomes very unstable, leading to inversion in severe cases. Seasoned crystallographers familiar with the concepts can successfully push the procedure to quite high 'B limits', whereas less experienced practitioners should follow the protocols very carefully. Please contact us for any details. Best - MM -------------------------------------------------------------------------------- Mischa Machius, PhD Associate Professor UT Southwestern Medical Center at Dallas 5323 Harry Hines Blvd.; ND10.214A Dallas, TX 75390-8816; U.S.A. Tel: +1 214 645 6381 Fax: +1 214 645 6353

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