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Amber in phenix
by R. Gasper-Schönenbrücher 12 Jul '16

12 Jul '16

Hi all, I am trying to run amber from phenix with a standard pdb file, no co-factors etc and struggle already at the phenix.AmberPrep script. For unknown reasons, the .prmtop file stays empty (0 bytes). I have tried to figure out from the amber python scripts, where the problem might be, but didn't find anything obvious (the "self.ns_names" variable stays empty) The leap log files states two problems: 1) ......Nonterminal, was not found in name map. (for every single amino acid) 2) FATAL: Atom .R<MET 1>.A<N 1> does not have a type. (for every single atom) which ends up in: "Failed to generate parameters Parameter file was not saved." There is no .map2 file generated. Phenix version: dev-2463 Amber: Ambertools 16 Every help is highly appreciated. Many thanks! Best, Raphael -- Raphael Gasper-Schönenbrücher Universität Bochum AG Proteinkristallographie, Lehrstuhl für Biophysik, NDEF 04/316 Universitätsstraße 150 44801 Bochum Germany Tel: +49 (0)234-32 27086 Fax: +49 (0)234-32 14762

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How to assign Half occupancy to metal ion in protein crystal
by Sharan Karade 08 Jul '16

08 Jul '16

Dear all, I am refining the protein structure and i want add metal ion in the structure, the site is present in between protein chain and its symmetry mate. when i added metal and refined, it was showing the high B factor and symmetry related metal on the same site. i want to assign the occupancy half and refine but in coot i am unable to do. Is there any method to do this. Thanks in Advance -- Sharan C/O Dr. J V Pratap Senior Research Fellow, CSIR-Central Drug Research Institute, Lucknow

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Question about restrain of a nonstandard peptide
by Yufan Wu 05 Jul '16

05 Jul '16

Dear Phenix Developers/Users, I have a question regarding how to generate a correct restrain for a whole nonstandard peptide and how do run refinement correctly. The nonstandard peptide in my structure is pepstatin A (IVA Val Val STA Ala STA). I manually put the pepstatin A in the density and generated the cif files for IVA and STA and run the refinement with them. After refinement, the whole pepstatin A explored as pieces, which I guess the program treated the pepstatin A as single amino acids. By the way, I also manual input the “LINK” information in the input pdb file as below, LINK C VAL L 3 N STA L 4 1555 1555 LINK N ALA L 5 C STA L 4 1555 1555 LINK C ALA L 5 N STA L 6 1555 1555 And also, when I use the “Real Space Refine Zone” by clicking two atoms for the whole pepstatin A in coot, it exploded again, although I input the same cif file in coot as well. The data quality is not good (2.9 A with CC1/2=12), thus it is difficult to place amino acid individually to fit the destiny. In the PDB, there are several structures containing the pepstatin A, such as 4TVG, 4AUC. They have the pepatatin A sequence as VVVXAX, but none of them lists the constrains. Would you please help me and let me know how can I continue with refinement? Please let me know if you need more information. Thank you vey much! Yufan Wu Regards, Yufan Wu The Plueckthun Lab www.bioc.uzh.ch/plueckthun <http://www.bioc.uzh.ch/plueckthun>Phone: +41 44 635 5574

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Glycan refinement in Phenix.real_space_refine
by Simonas Masiulis 05 Jul '16

05 Jul '16

Hi, I want to refine N-linked glycans into an EM density using Phenix.real_space_refine, but it seems the rings get distorted. Does anybody know how to fix this (e.g., is there a way to provide a .cif file)? Thanks a lot! Simonas

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.cif file created by Jligand for used in phenix.model_vs_data
by luzuok 05 Jul '16

05 Jul '16

Dear all, The protein was covalently linked by my ligand and I used JLigand to generate the link record and the .cif file. This file can be used in Refmac successfully. But the .cif file cannot be recognized by phenix.model_vs_data nor phenix.refine. The program runs with the following message: Sorry: Fatal problems interpreting model file: Number of atoms with unknown nonbonded energy type symbols: 19 Please edit the model file to resolve the problems and/or supply a CIF file with matching restraint definitions, along with apply_cif_modification and apply_cif_link parameter definitions if necessary. Any suggestions how to do this would be greatly appreciated. Another question is, how can I generate a restraints file for COOT to do real space refinement? The .cif file is imported in COOT, but when I do real space refinement, the link bond still takes apart. Best wishes! Lu -- 卢作焜南开大学新生物站A202 Lu Zuokun, Ph.D. Candidate College of Life Science, Nankai University

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iNEXT news
by Anastassis Perrakis 05 Jul '16

05 Jul '16

Dear all, A new access modality has now been open in iNEXT (http://www.inext-eu.org <http://www.inext-eu.org/>) "From macromolecular sample to X-ray data collection” This novel access modality, hosted at the EMBL Hamburg and Grenoble Units, will provide transnational access to hands-on assistance for sample characterization and crystallization trials, leading to structural data via X-ray crystallography and/or solution small angle scattering. The users are expected to have a macromolecular sample that has already underwent some initial characterisation, and ideally to have performed initial crystallisation trials with promising results. If users cannot obtain such data in their home laboratory, they can first request a 'Structural Audit' via iNEXT. This modality can provide a report that can be automatically included to this application for pushing the project forward towards obtaining more extensive structural data. Successful "Structural Audits" will be fast-tracked towards extended support via this or other modalities. Please do note, that a small proportion of iNEXT access modalities is also open for non-European users, other than the countries listed in our web site. We also want to remind you that most iNEXT access modalities are now open: Structural Audit (sample mail-in for quality assessment for structural biology studies or SAXS-only characterisation) Mail-in characterization of a macromolecular sample, including stability, oligomeric state, crystallization and SAXS; also NMR and negative stain EM for suitable samples. Enhanced Support (Dedicated expert help for specific structural biology projects) From macromolecular sample to X-ray data collection Hands-on assistance for sample characterization and extensive crystallization trials, leading to structural data via crystallography solution and/or small angle scattering. Cryo-EM sample optimisation Hands-on assistance in optimizing a sample for single particle EM; a good quality preliminary characterization by negative stain is the minimal entry point. Macromolecular interactions Hands-on assistance for quantifying the steady state and transient kinetics underlying macromolecular interactions, by fluorescence methods, MALLS, SPR, ITC, MST High-end Data Collection (For experts: access to high-field NMR, X-ray and high-resolution EM equipment) Synchrotron data Access to synchrotron beamlines for X-ray Crystallography and/or SAXS, for translational research project(s); for single or multiple visits and research groups. High-field NMR Access for experienced NMR-scientists to visit host institutes for acquiring solution or solid state NMR spectra on high-field instruments. High-resolution EM Access to state of the art electron microscopes for single particle, tomography and correlative light and electron microscopy (CLEM). A specific note for synchrotron data applications: projects can request multiple visits for a combination of MX, SAXS, and remote access in multiple sites, and the access can be split in several visits. A “project” should have a scientific theme of translational value, but is not necessarily limited to a specific ’target'. Multiple macromolecules and complexes can be pooled under the same proposal, as long as the research theme can be described in a concise and consolidated manner, with clear statements about availability samples and the reasoning behind specific experiments. "Structural Audit" or "From macromolecular sample to X-ray data collection"? Structural Audit contains basic crystallisation screening, MALLS and SAXS; if you already have such data, we recommend that you proceed to the Enhanced Support. Please do note however, that labs with strong experience in the field, should preferably aim for the High-end Data Collection; these modalities are aiming to help labs new to X-ray studies. Please also note that these are not similar to the old Biostruct-X requests for access to crystallisation facilities only, but are meant to be accessed as a coherent package. Please note that "Structural Audit” review is very rapid and the experiment contains no physical presence, so the application and experiment turnover can be rapid. For questions about X-ray methods please mail me; for NMR and EM related questions please mail Hans H.L.J.Wienk.AT.uu.nl Best regards, Tassos

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Post-doctoral position in membrane protein structure and function, University of Oxford, UK
by Maike Bublitz 22 Jun '16

22 Jun '16

Dear all, a post-doctoral position is available in the research group of Associate Prof. Maike Bublitz at the Department of Biochemistry, University of Oxford. The project aims to understand the structure and function of microbial membrane transport proteins identified as potential new drug targets, using a combination of state-of-the-art structural (X-ray crystallography, cryo-EM) and biochemical/biophysical techniques. Applicants should hold a PhD in a relevant subject area, such as membrane protein biochemistry or structural biology. Experience in native or recombinant membrane protein expression, purification and either structural determination or functional analysis using biochemical and biophysical techniques is essential. Ability to work in a team as well as contribute to supervision activities and excellent verbal and written communication skills are expected. Experience in protein X-ray crystallography and/or cryo-EM is an advantage. To apply for this role and for further details, including the job description and selection criteria, please click on the link below: https://www.recruit.ox.ac.uk/pls/hrisliverecruit/erq_jobspec_details_form.j… Applications for this vacancy are to be made online by 18th July 2016. Informal enquiries can be sent to maike.bublitz(a)bioch.ox.ac.uk<mailto:[email protected]>. Best regards, Maike ************************************************* Dr. Maike Bublitz Associate Professor of Microbial Biophysics Department of Biochemistry University of Oxford South Parks Road Oxford OX1 3QU United Kingdom phone: +44 (0)1865 613221 maike.bublitz(at)bioch.ox.ac.uk<http://bioch.ox.ac.uk>

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Just before crystallographic structure deposition
by cedric bauvois 22 Jun '16

22 Jun '16

Dear all, At the end of model-building, several modifications are often required for submission (remove some water molecules, deal with unusual bad bond, ...). After doing so, is there any way in phenix to generate a new pdb file containing updated informations (r_factors, bonds, angles, model content,...) ? Thanks a lot Cedric

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Deadline for registrations for the GRC on Diffraction Methods in Structural Biology is this Sunday.
by Edward Snell 16 Jun '16

16 Jun '16

Last chance to register for the Gordon Research Conference on Diffraction Methods in Structural Biology to be held at Bates College in Lewiston, Maine, July 17th-22nd 2016. The conference is themed around "Probing the structure and dynamics of macromolecules" and details of the program are at https://www.grc.org/programs.aspx?id=11655. The closing date for applications is this Sunday June 19th. Please join us in Maine this summer for the 40th anniversary of this meeting. Eddie Snell and Arwen Pearson Edward Snell Ph.D. CEO Hauptman-Woodward Medical Research Institute Assistant Prof. Department of Structural Biology, University at Buffalo 700 Ellicott Street, Buffalo, NY 14203-1102 Phone: (716) 898 8631 Fax: (716) 898 8660 Skype: eddie.snell Email: esnell(a)hwi.buffalo.edu Heisenberg was probably here!

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Project Scientist positions for computational methods
by Nicholas Sauter 13 Jun '16

13 Jun '16

Two Project Scientist positions are available in my group in the *Molecular Biophysics and Integrated Bioimaging* <http://biosciences.lbl.gov/divisions/mbib/> (MBIB) Division at Lawrence Berkeley National Lab. *Bioimaging Project Scientist* Position Summary: We have an exciting opportunity for a Bioimaging Project Scientist who will apply neuromorphic computing techniques to structural biology problems in X-ray diffraction, CryoEM, and CryoET. This will be a cross-disciplinary effort between MBIB and the Computational Research (CRD) Division at Lawrence Berkeley National Laboratory. The research group will include investigators Nick Sauter (X-ray Crystallography), Karen Davies (CryoEM/ET), and Chao Yang (Scalable Solvers). Specific Responsibilities: - Investigate how to apply deep learning algorithms to specific data processing and data interpretation problems in structural biology. - Implement convolutional neural network (CNN) code on neuromorphic computing hardware such as the IBM TrueNorth chip. Example problems include the identification of positive diffraction events in X-ray free-electron laser diffraction, conformational classification in CryoEM single particle reconstruction, and the identification of 3D sections for CryoET subtomogram averaging. - Use tools such as MatConvNet, CAFFE, THEANO or TensorFlow to construct and train CNNs that can be used to optimally classify experimental data. Required Qualifications: - Research experience in Structural Biology, with expertise in allied fields such as Bioinformatics, Mathematics, Computer Science, or Engineering (Ph.D. + 3 years or equivalent) - Strong background in image analysis and machine learning, including neural networks. - Working knowledge of image classification and/or other image processing techniques. - Proficient programming skills in MATLAB and/or Python. - Working knowledge of performance optimization for scientific codes. *Algorithm Developer Project Scientist* Position Summary: We are seeking an algorithm developer for the increasingly complex analysis of large diffraction datasets in structural biology. Current projects utilize XFEL crystallography and spectroscopy to investigate the photosynthetic mechanism of water splitting and to probe other metalloenzyme reactions. We also wish to test whether diffuse scattering can reveal correlated atomic motions in crystals. Many problems remain to be solved, including the details of how to optimally merge datasets from thousands of crystals. Our software development projects (including packages such as DIALS <http://dials.lbl.gov/> and cctbx.xfel <http://cci.lbl.gov/xfel>) have been highlighted in several high-impact publications listed HERE <http://biosciences.lbl.gov/profiles/nicholas-sauter>. Specific Responsibilities: - Continue work on the DIALS data integration suite. - Test new algorithms for optimally characterizing and merging data from serial crystallography experiments. - Analyze anomalous scattering from metalloenzymes using XFEL diffraction. - Investigate whether diffuse scattering can reveal correlated atomic motions in crystals. Required Qualifications: - Expertise in one or more computational techniques including, but not limited to, ray tracing to test underlying physical models of the diffraction, Bayesian approaches for refining model parameters, macromolecular modeling and refinement, neural networks for interpreting image features, as well as signal processing and denoising methods. - Extensive data analysis experience in crystallography or from more general bioimaging backgrounds are welcome. - We particularly encourage strong mathematical intuition and a track record of bringing new ideas and tools to fruition, as evidenced through written publication and clear presentation. Candidates should send an expression of interest, CV, and list of three references to Nick Sauter, nksauter(a)lbl.gov*. *Further details are posted at https://lbl.taleo.net/careersection/2/jobdetail.ftl?lang=en&job=82554. Nicholas K. Sauter, Ph. D. Computer Staff Scientist, Molecular Biophysics and Integrated Bioimaging Division Lawrence Berkeley National Laboratory 1 Cyclotron Rd., Bldg. 33R0345 Berkeley, CA 94720

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