- phenixbb - phenix-online.org

Alternative to AlphaFold2?
by Chip Lesburg 22 Sep '22

22 Sep '22

Hi PHENIX users, At this past summer's Diffraction Methods GRC meeting<https://www.grc.org/diffraction-methods-in-structural-biology-conference/20…>, Tom Terwilliger presented the utility of incorporating AlphaFold2 predictions during structure fitting and rebuilding. I wonder if anyone has experience using that or an alternative such as OmegaFold<https://www.biorxiv.org/content/10.1101/2022.07.21.500999v1> or OpenFold<https://github.com/aqlaboratory/openfold>? Are any of these easier or harder to get set up? Chip [cid:153156_edd5022b-de61-48a6-bf68-1a41de35ba89.png] Charles Lesburg Vice President, Structural Biology M 908-265-2064 301 Binney Street, Cambridge, MA 02142 odysseytx.com This message is for the named person's use only. It may contain confidential, proprietary or legally privileged information. If you receive this message in error, please immediately delete it and all copies of it from your system, destroy any hard copies of it and notify the sender. ODYSSEY THERAPEUTICS, INC. ("ODYSSEY THERAPEUTICS") reserves the right to monitor all e-mail communications through its networks. ODYSSEY THERAPEUTICS cannot be committed by this e-mail or warrant the accuracy or validity of any information presented. Any views expressed in this message are those of the individual sender.

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Question about occupancy and 2Fo-Fc and Fo-Fc maps
by Vatsal Purohit 20 Sep '22

20 Sep '22

Hi everyone, I had 2 questions regarding occupancy and maps generated in ligand-bound regions for various ligand models potentially present in the structure: 1. I’ve been working with some 2.0 angstrom structures and trying out refinements with 2 sets of bound ligands at varying occupancies (at the same active site) to get an approximate idea of their relative populations in the structure. For one set of ligands, I observe 2Fo-Fc density in regions uniquely occupied by them even when their occupancy is zero. Could there be a reason why this is the case? 2. Additionally, I observe red Fo-Fc density in the same region when the occupancy is set to 1.0. It disappears at lower occupancies of 0.7 indicating that a lower population of this ligand is present. However, when the occupancy is very low, we don’t see an equivalent green Fo-Fc density popping up in the same region. Could there be a reason for why the red Fo-Fc density at high occupancy doesn’t translate to green Fo-Fc for the same region at low occupancy? Any information or resources that could give me more insight into this question would be really helpful! Regards, Vatsal

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General interest article
by John R Helliwell 09 Sep '22

09 Sep '22

Dear Colleagues, I imagine you will find the article “The 4Rs and crystal structure analysis: reliability, reproducibility, replicability and reusability” of interest. The weblink is https://journals.iucr.org/j/issues/2022/05/00/dv5002/index.html The article is open access. It is a Teaching and Education article in J Appl Cryst. Best wishes, John Emeritus Professor John R Helliwell DSc

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Runtime error : Bond distance
by Luca Pellegrini 06 Sep '22

06 Sep '22

Phenix real space refine (dev 4704) crashes with: RuntimeError : Bond distance > max_reasonable_bond_distance: 67.4676 > 50: I’ve found various reports of this error in the bb but no (to me) clear solution, only one suggestion to increase the max_reasonable_bond_distance (Nov 2017). I tried setting excessive_bond_distance_limit (I guess is the same) to 999 but with no success as Phenix stops with the same error. Any help on how to fix this gratefully received. Best wishes, Luca

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Reference model restraints
by Luca Pellegrini 01 Sep '22

01 Sep '22

Hello, Phenix.real_space_refine keeps pushing a residue out of density so I'd like to restrain it to its current position. Can you please let me know how to implement in the GUI the first example at point 14 at https://phenix-online.org/documentation/reference/real_space_refine.html#us… phenix.real_space_refine model.pdb map.mtz \ reference_coordinate_restraints.enabled=true \ reference_coordinate_restraints.selection="chain A and resseq 12:21" \ reference_coordinate_restraints.sigma=0.05 Best wishes, Luca Luca Pellegrini, PhD Department of Biochemistry University of Cambridge Cambridge CB2 1GA UK

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Phenix website downtime
by Billy Poon 01 Sep '22

01 Sep '22

Hi everyone, There was some networking issue which caused the Phenix website to be down for several hours. The site should be back to normal, but please let us know if you have any issues. Thanks! -- Billy K. Poon Research Scientist, Molecular Biophysics and Integrated Bioimaging Lawrence Berkeley National Laboratory 1 Cyclotron Road, M/S 33R0345 Berkeley, CA 94720 Fax: (510) 486-5909 Web: https://phenix-online.org

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RNA structural biology position (Scientist-Sr.Scientist) at Arrakis Therapeutics
by Elena Menichelli 25 Aug '22

25 Aug '22

Dear all, We have an open position for an RNA structural biologist at Arrakis Therapeutics (Boston, MA area). The ideal candidate will have a background in structural characterization of RNA (X-ray crystallography, cryo-EM or atomic force microscopy) and a passion for developing small molecules that target RNA in a very collaborative environment. Please feel free to visit Arrakis’ website for a more detailed job description and to reach out to me for additional information and informal discussion. https://arrakistx.com/careers/current-openings/ With best regards, Elena ******* Elena Menichelli, PhD | Head of Structural Biology emenichelli(a)arrakistx.com<mailto:[email protected]> | www.arrakistx.com<http://www.arrakistx.com/>

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Launch of IUCrData Raw Data Letters: Editorial
by John R Helliwell 24 Aug '22

24 Aug '22

Dear Colleagues, I imagine you will be interested to know of the launch of IUCrData’s Raw Data Letters. The Main Editor is Dr Loes Kroon Batenburg. See https://forums.iucr.org/viewtopic.php?f=39&t=449&p=729#p729 Greetings, John Emeritus Professor John R Helliwell DSc Chair of IUCr CommDat

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phenix.refine command lane xyz restrains
by Błażej Bagiński 24 Aug '22

24 Aug '22

Dear Phenix community, lately I started toying with the terminal version of our favourite refinement software (on kubuntu linux). I'm refining a structure with a ligand that is not in the refmac database (.cif file needed), and I couldn't find anything on how to implement xyz coordinates restraints for the procedure. In other words, I have a ligand that I built into the polder map and I want to tell the software "do not change the positions in space of these atoms". How can I do that? Also, side question: why there are three different(?) versions of command line phenix.refine for every phenix installation? What is the difference between them? REMARK 6 I followed the online guide for "Refinement at high resolution" on my 1,2~1,3A structure and the results were surprisingly nice, I'd say potentially even better than usually used parameters in GUI (5 cycles both). Kind regards, Blazej

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Postdoctoral Research Associate in the Structural Biology of Supramolecular Protein Assemblies
by Owen Davies 19 Aug '22

19 Aug '22

Dear all, I would like to advertise a postdoctoral position that is currently available in my lab at the Wellcome Centre for Cell Biology, University of Edinburgh, UK (https://www.wcb.ed.ac.uk/research/owen-davies). This position is for an initial period of three years (with possibility to extend), to work on the integrative structural biology of the synaptonemal complex. The synaptonemal complex is a supramolecular protein structure that assembles during meiosis to facilitate homologous chromosome synapsis and crossover formation. Its immense structure, of many micrometers in length, is formed through the combination of at least three unique self-assembling protein systems, which individually form lattice-like arrays, para-crystalline filaments and 'intermediate filament'-like fibres. This position aims to determine the molecular structure of the human synaptonemal complex and its constituent complexes through their reconstitution from recombinant proteins. This will be achieved through a cutting-edge structural biology approach, involving cryo-EM single particle reconstruction and tomography, structure solution of components by X-ray crystallography, solution biophysics (including X-ray and light scattering, and single-molecule biophysics), and the integration of experimental findings by advanced computational modelling of structures and assembly dynamics. The post is funded by a Wellcome Senior Research Fellowship, and will be hosted in a well-equipped and well-funded lab, which includes the following: Extensive biochemical equipment (including numerous Akta Pure systems, SEC-MALS etc) Protein production and characterisation facility (https://www.ed.ac.uk/biology/research/facilities/edinburgh-protein-producti…) State-of-the-art biophysics equipment (including C-trap optical tweezers) In-house TEM, SEM and newly upgraded cryo-EM facility (https://www.ed.ac.uk/biology/research/facilities/electron-microscopy) Regular time on macromolecular crystallography and SAXS synchrotron beamlines at Diamond Light Source (https://www.diamond.ac.uk) Regular cryo-EM time on Titan-Krios microscopes at Diamond Light Source (https://www.diamond.ac.uk) and Jeol microscopes at the Scottish Centre for Macromolecular Imaging (https://www.gla.ac.uk/researchinstitutes/iii/cvr/facilities/scmi/) Local provision of high-performance GPU computation for cryo-EM, modelling and molecular dynamics This position provides a unique opportunity for a highly enthusiastic applicant to perform transformative research through an integrative approach that is directed towards the new era of structural biology that address protein assemblies at a cellular scale. The successful candidate will lead this project (including several PhD students), and will be fully supported in applying for postdoctoral research fellowships within the lab, and independent research positions at the end of the postdoc. In suitable cases, at least part of the project, or a new project to be started during the employment, could be taken by the successful candidate as the basis for their future research career. Please see the following manuscripts for examples of our previous work: https://www.nature.com/articles/s41594-021-00636-z https://www.nature.com/articles/s41594-018-0078-9 https://www.nature.com/articles/s41467-018-07794-7 https://www.science.org/doi/10.1126/sciadv.abb1660 https://elifesciences.org/articles/60175 Full publication list available at https://www.ed.ac.uk/profile/dr-owen-davies The advert for the position is available via the following link: https://www.jobs.ac.uk/job/CRX346/postdoctoral-research-associate-in-the-st… The application deadline is 6th September, and candidates should apply by following the 'apply' link on the above advert. Please feel free to contact me directly (Owen.Davies(a)ed.ac.uk<mailto:[email protected]>) for informal discussions and additional information. Best wishes, Owen. Dr Owen Davies Wellcome Senior Research Fellow Wellcome Centre for Cell Biology University of Edinburgh Michael Swann Building Max Born Crescent Edinburgh EH9 3BF United Kingdom The University of Edinburgh is a charitable body, registered in Scotland, with registration number SC005336. Is e buidheann carthannais a th' ann an Oilthigh Dh?n ?ideann, cl?raichte an Alba, ?ireamh cl?raidh SC005336.

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Inability to connect the N and C terminal of peptide to form a peptid bond of a circular peptide structure
by Jiang Xu 14 Aug '22

14 Aug '22

Hello Guys, I have a circular peptide structure solved from Xtal. The peptide is actually a circular peptide that has the N terminal and C terminal joined together by a peptide bond. When refining the structure, I had a problem getting the C-N terminal (between G34 and S2) joined together by the peptide bond. I even made a link between the C terminal carbon atom and N terminal N atom in coot and used this model as the input model to do the refinement using Phenix.refine. It seemed that the program didn't consider the link made in coot as a valid bond and intentionally avoid forming a bond between the C atom and the N atom. So, how can I solve this problem? Thank you, Best regards, Jiang Lin Chen Lab University of Southern California P.S. coot manually made link between the C and N terminal [image: unnamed.jpg] After refinement [image: unnamed (1).jpg]

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Postdoc Opportunity - Multidataset X-ray Crystallography, Computational Structural Biology, & Protein Allostery - Upper Manhattan, New York City
by Keedy, Daniel 09 Aug '22

09 Aug '22

Hello Phenix community, The Keedy Lab at the CUNY Advanced Science Research Center in New York City has a funded Postdoctoral Scholar position available immediately. We seek applications from individuals with experience in computational biology, computer science, software development, biochemistry, biophysics, or a related area. Details of research projects and career training will be tailored to the goals of the successful applicant. Research: The Keedy Lab is interested in the interplay between protein sequence, conformational heterogeneity, and biological function. Using a unique combination of avant-garde computational and biophysical approaches, we aim to elucidate the conformational ensembles of proteins and to understand how they are shifted by perturbations, including temperature, pressure, mutations, ligands, protein:protein interactions, to control biological function. The successful applicant for this open position will join these efforts by developing and using new computational approaches to exploit families of related structures, extract hidden signatures of conformational heterogeneity, and explore how changes to amino acid sequence rewire protein allosteric networks. Location: The CUNY Advanced Science Research Center (https://asrc.gc.cuny.edu) is a cutting-edge research institution, perched atop a hill overlooking Harlem in New York City. Alongside its sister research building, the City College of New York’s Center for Discovery and Innovation, the ASRC sits in an oasis of green amidst upper Manhattan. The ASRC Structural Biology Initiative features eight tenure-track and research-track faculty members, pursuing diverse research problems using X-ray diffraction, mass spectrometry, cryo-EM, NMR, solution biophysics, and advanced microscopy. The ASRC is immediately adjacent to the New York Structural Biology Center, a consortium of CUNY and eight other New York academic institutions with world-class facilities, and is just 70 miles from Brookhaven National Laboratory, featuring the National Synchrotron Light Source II – the brightest synchrotron light source in the United States. You can read more about the Keedy lab here: https://keedylab.org Please officially apply for the position here: https://www.rfcuny.org/careers/postings?pvnID=RC-2207-004956 You may also email me directly to ask questions or discuss. I look forward to hearing from you! Best regards, Daniel Keedy — Daniel A. Keedy, PhD Assistant Professor Structural Biology Initiative, CUNY Advanced Science Research Center Department of Chemistry and Biochemistry, City College of New York Biochemistry, Biology, and Chemistry PhD Programs, CUNY Graduate Center dkeedy(a)gc.cuny.edu<mailto:[email protected]> | https://keedylab.org | 919-724-6064

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Naming/refining glycosylation
by Tynan Young 09 Aug '22

09 Aug '22

Hi all, I am having issues with naming of glyco- groups and refining my glycosylated EM structure in Coot. I have noticed that many models use the same chain ID for the glyco- groups as the chain ID they are attached to (i.e. NAG/B/1301 would be linked to ASN/B/121). When working with the model in Coot, I would like to refine only the ASN 121 and the NAG 1301 attached to it. However, due to the naming of the glyco- group, Coot will refine residues 121-1301. Not only is this very time-consuming, but it will disrupt the rest of the model - which I do not want to do. If I change the chain ID of the glyco- group to an altogether different chain ID, then I can no longer refine both the side chain and the glyco- group. Is there some naming scheme that avoids this issue? Any help is greatly appreciated. Thank you. Tynan ---------------------------------------------------------------------- ------------------------------------------------------------ -SECURITY/CONFIDENTIALITY WARNING- This message and any attachments are intended solely for the individual or entity to which they are addressed. This communication may contain information that is privileged, confidential, or exempt from disclosure under applicable law (e.g., personal health information, research data, financial information). Because this e-mail has been sent without encryption, individuals other than the intended recipient may be able to view the information, forward it to others or tamper with the information without the knowledge or consent of the sender. If you are not the intended recipient, or the employee or person responsible for delivering the message to the intended recipient, any dissemination, distribution or copying of the communication is strictly prohibited. If you received the communication in error, please notify the sender immediately by replying to this message and deleting the message and any accompanying files from your system. If, due to the security risks, you do not wish to receive further communications via e-mail, please reply to this message and inform the sender that you do not wish to receive further e-mail from the sender. (LCP301) ------------------------------------------------------------

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Phenix and coot
by Cygler, Miroslaw 08 Aug '22

08 Aug '22

Hi, The phenix connection to graphics software stopped working on my laptop after a refine job got suspended and I had to force quit the program (abort function did not work). Now when I run refinement the coot does not start automatically. How can I reconnect phenix with coot and pymol? Thanks, Mirek

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Drug Discovery Scientist opening Vanderbilt University
by Harp, Joel M 13 Jul '22

13 Jul '22

Drug Discovery Scientist Position An opening is available in the drug discovery laboratory of Dr. Stephen Fesik for a candidate with experience in the field of protein x-ray crystallography or NMR. Responsibilities will include protein production, fragment screening by NMR, and all aspects of x-ray crystallography including preparation of protein-ligand complexes, crystallization, home/synchrotron data collection, and structure determination. Additional experience in molecular biology including construct design, cloning, site-directed mutagenesis and modeling is a plus but not required. The ideal candidate should be self-motivated and be able to communicate efficiently in a highly collaborative environment. Please send cv to jason.phan(a)Vanderbilt.Edu<mailto:[email protected]> The Vanderbilt campus is located in Nashville, Tennessee. Also known as Music City, Nashville is a fast growing and dynamic environment with plenty of cultural attractions and opportunities for outdoor recreation. ________________________________ To unsubscribe from the CCP4BB list, click the following link: https://www.jiscmail.ac.uk/cgi-bin/WA-JISC.exe?SUBED1=CCP4BB&A=1<https://nam04.safelinks.protection.outlook.com/?url=https%3A%2F%2Fwww.jiscm…>

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Postdoctoral position in drug discovery
by Harp, Joel M 12 Jul '22

12 Jul '22

Postdoctoral position in drug discovery An opening is available in the drug discovery laboratory of Dr. Stephen Fesik for a post-doc in the field of protein x-ray crystallography. Responsibilities will include protein production, fragment screening by NMR, and all aspects of x-ray crystallography including preparation of protein-ligand complexes, crystallization, home/synchrotron data collection, and structure determination. Additional experience in molecular biology including construct design, cloning, site-directed mutagenesis and modeling is a plus. The ideal candidate should be self-motivated and be able to communicate efficiently in a highly collaborative environment. Please send cv to jason.phan(a)Vanderbilt.Edu<mailto:[email protected]>

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Reminder: Phenix user workshop at the ACA2022 in Portland
by Dorothee Liebschner 05 Jul '22

05 Jul '22

Dear Colleagues, The Phenix developers will be holding a day-long satellite workshop on July 29th, prior to the ACA meeting in Portland, Oregon. This Phenix user workshop will focus on using predicted models for crystallography and cryo-EM. *Please note: Registration closes on July 8th!* The format of the workshop will be demos of the use of Phenix programs combined with slides to explain the theory. We expect an interactive meeting where attendees can ask questions for the Phenix team to answer. Topics will cover aspects of macromolecular structure determination in Phenix. For registration, see the ACA 2022 website: https://www.acameeting.com/aca-wk2. You need to register for the main meeting in order to participate in the workshop. This is an in-person workshop (no hybrid option). Lecturers: Pavel Afonine, Dorothee Liebschner, Billy Poon, Tom Terwilliger Looking forward to seeing you there! The Phenix team Detailed Program: 8:00 Welcome: Introduction to Phenix, Introduction to the GUI, set up Phenix 8:45 Overview -- Strategy for X-ray or Cryo-EM structure determination using AlphaFold models (lecture) 9:15 Predicting your structure with AlphaFold and trimming it with ProcessPredictedModel (demo) 9:45 Solving an X-ray structure automatically by MR with PredictAndBuild (demo with pre-computed data) 10:15 Break 10:45 Evaluating X-ray data with Xtriage 11:00 Xray refinement (lecture) 11:30 Xray refinement with AlphaFold reference models (demo) 12:00 Lunch 13:00 Ligands (lecture & demo) 13:30 Cryo-EM Data evaluation with Mtriage (short lecture & demo) 13:45 Cryo-EM map manipulations, map improvement with LocalAnisoSharpen and ResolveCryoEM (demo) 14:30 Break 15:00 Automatic cryo-EM map interpretation with PredictAndBuild (demo with pre-computed data) 15:30 Cryo-EM refinement (lecture and demo) 16:00 Model validation (lecture & demo) 16:30 Q&A 16:50 finish: workshop survey and wrap up -- Research Scientist, Molecular Biophysics and Integrated Bioimaging Lawrence Berkeley National Laboratory 1 Cyclotron Road, M/S 33R0345 Berkeley, CA 94720 Tel: (510) 486-5709 Fax: (510) 486-5909 Web: https://phenix-online.org

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mmCIF output by phenix.refine
by Mark Saper 30 Jun '22

30 Jun '22

Why does .CIF file output by phenix.refine contain all of the -h -k -l reflections. The Bijvoet reflections are already contained in the _refln.pdbx_F_minus column of the +h +k +l reflections. When OneDep at PDB reads in these files, it finds ‘?’ in about half of the reflections, and assigns them a status of ‘x': Warning: (data block=1): 36739 reflections have status assigned as '?' (changed to 'x') Warning: (data block=1): 36739 reflections have wrong status. Not in list(o,f,x,-,<,h,l) Is this the correct behavior? My space group is 19. Thanks, Mark _____________________ Mark A. Saper, Ph.D. Associate Professor Emeritus of Biological Chemistry University of Michigan Medical School saper(a)umich.edu | +1 734 276 6505

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3x4 matrix for wwPDB deposition
by Christian Tüting 28 Jun '22

28 Jun '22

Hi Phenix Dev team and mailing list recipients, i have a question regarding the 4x3 matrix in the wwPDB deposition assembly tab. I am wondering, if there is an easier way, than what I am currently doing. This is my current workflow: # get the map symmetry phenix.map_symmetry symmetry=O map.mrc # apply symmetry on monomer phenix.apply_ncs mono.pdb symmetry_from_map.ncs_spec # get biomt from complex phenix.find_ncs apply_ncs.pdb # isolate wwPDB deposition 3x4 matrix awk '{print substr($0, 25)}' find_ncs.biomt > 3x4_matrix And this feels a bit redundant, as I already have the symmetry operation directly from the beginning, but the monomeric localization is missing. Is there an easier way to get the 3x4 matrix? This is still fast, so this is fine, but maybe there is an easier, single line solution. Best Christian

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Running phenix into a M1 apple processor
by Armando Albert 24 Jun '22

24 Jun '22

Dear all, Is there any version of phenix for the new M1 apple processors? Thank you Armando

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Building DNA into the cryo-EM map density
by Yangqi Gu 21 Jun '22

21 Jun '22

Dear PHENIX users and developers, I am currently building a model for a cryo-EM map of a helical complex. I could build the protein easily into the map. However, the map also contains a long chain of DNA density, I am wondering what could be the best way to build this DNA model? I have no previous experience building models with a DNA complex, therefore any suggestion would be helpful! Best. Yangqi -- Yangqi Gu Ph.D. Yale University, West Campus

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ACA hotel block closing June 17
by Anna Gardberg 14 Jun '22

14 Jun '22

Dear Colleagues, The ACA annual meeting in Portland is fast approaching. The meeting will be held from July 29 - August 3, 2022. The hotel room block at the Marriott Downtown Waterfront will be closing on June 17th. Book your room today <https://book.passkey.com/event/50263127/owner/3508/home>! Register for the meeting <https://www.acameeting.com/registration-info> and consider taking one of the workshops <https://www.acameeting.com/workshops> on July 29. WK1: Applications of Small Angle Scattering to Structural Biology: An Introduction WK2: Crystallographic and cryo-EM Structure Solution with Phenix WK3: Cryo-Electron Tomography: State of the Art Methods WK4: Hands-on Single-Particle Cryo-EM Data Analysis with Cryo EDU WK5: CryoEM Sample Preparation Training using Center Merit Badges WK6: Advanced Software Tools for Single Crystal Diffraction WK7: Visualizing Structure WK8: Microcrystal Electron Diffraction (MicroED) If you are already registered for the proximally located M&M conference, you can register for the ACA workshops and/or an ACA one day pass <https://acas.memberclicks.net/index.php?option=com_mcform&view=ngforms&id=2…> . We look forward to seeing you in Portland! The 2022 Annual Meeting Committee

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phenix.douse, resampled map?
by Guenter Fritz 12 Jun '22

12 Jun '22

Dear Pavel, dear all, I was running phenix.douse on a map from resolve. It works very nicely. As far as I understand phenix.douse generates a resampled map with finer grid for water picking. Is there an option to write this resampled map out? Best regards, Guenter

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high R-value with resolve_cryo_em
by Daniel Larsson 11 Jun '22

11 Jun '22

Hi all, I tried to do density modification using the resolve_cryo_em tool. The resolution improves quite a lot from around 2.60 to around 2.35 and the density looks significantly better than the autorefined original map. However, the R-values is close to 0.5, which seems very high. How should the R-value generated by this tool be interpreted? It is very poorly documented and not mentioned in the paper or on the manual page, but Tom Terwilliger mentioned in a workshop that “low number is good” and “point two-four is a very good number, point five is not a good number”, which makes me worried. Regards, Daniel När du har kontakt med oss på Uppsala universitet med e-post så innebär det att vi behandlar dina personuppgifter. För att läsa mer om hur vi gör det kan du läsa här: http://www.uu.se/om-uu/dataskydd-personuppgifter/ E-mailing Uppsala University means that we will process your personal data. For more information on how this is performed, please read here: http://www.uu.se/en/about-uu/data-protection-policy

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Postdoctoral position in Manchester
by Harshwardhan Poddar 08 Jun '22

08 Jun '22

Hi everyone, There is a PostDoc position available in the laboratory of Prof Nigel Scrutton based at Manchester Institute of Biotechnology. This is an exciting opportunity to characterise some newly discovered light-sensitive proteins using time-resolved structural techniques. More details can be found here- Research Associate in Structural Biology : Manchester Institute of Biotechnology (MIB) | | | | | | | | | | | Research Associate in Structural Biology : Manchester Institute of Biotechnology (MIB) | | | | Best Harshwardhan

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Structural Biology position at Odyssey Therapeutics (Boston MA)
by Chip Lesburg 06 Jun '22

06 Jun '22

Opportunity for a Senior/Principal Scientist at Odyssey Therapeutics in Boston MA. We are seeking a highly motivated and skilled Structural Biologist to join the Odyssey team at our site in Boston where you will be a key contributor to the structural enablement of pipeline discovery projects. You will employ cutting-edge structural techniques such as cryo-EM and X-ray crystallography in a cost-effective, efficient manner. You will use your expertise to better understand mechanisms of action and structural aspects of protein-protein and protein-ligand interactions, and to guide protein therapeutic design. You will oversee the production of quality proteins in support of biophysical and structural analyses. Working closely within therapeutic project teams, you will determine and communicate the structures of both protein-small molecule complexes and multiprotein complexes. In this primarily lab-based role, you will be a key contributor to the application of internal and external resources and capabilities necessary to drive biophysics and structural biology efforts. More information, including responsibilities and desired skills, can be found at: https://boards.greenhouse.io/odysseytherapeutics/jobs/4538034004 Chip Lesburg [cid:153156_edd5022b-de61-48a6-bf68-1a41de35ba89.png] Charles Lesburg Vice President, Structural Biology M 908-265-2064 301 Binney Street, Cambridge, MA 02142 odysseytx.com This message is for the named person's use only. It may contain confidential, proprietary or legally privileged information. If you receive this message in error, please immediately delete it and all copies of it from your system, destroy any hard copies of it and notify the sender. ODYSSEY THERAPEUTICS, INC. ("ODYSSEY THERAPEUTICS") reserves the right to monitor all e-mail communications through its networks. ODYSSEY THERAPEUTICS cannot be committed by this e-mail or warrant the accuracy or validity of any information presented. Any views expressed in this message are those of the individual sender.

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Problem with rebuild_predicted_model
by Andrei Moiseenko 04 Jun '22

04 Jun '22

Dear all, I am trying to build the model with Alphafold2 using Dock and Rebuild and encountered some issue with rebuild_predicted_model. It does not rebuild the model telling that: "Unable to morph model...may not match exactly in chain ID or residue numbers. No morphed model obtained... No docked model to work with." I use the model predicted with Alphafold2 google colab and the cryoem map with 3.5A resolution boxed around the protein of interest. The process_predicted_model and dock_predicted_model run successfully, giving the single-chain model which nicely fits into the map (40 of 300 residues are excluded due to low LDDT). The chain ID in the docked model is indeed different from predicted model: the predicted model has one chain A, but the docked one has A1. However, manually changing the chain ID either in the predicted or in the docked model does not resolve the issue. Manual runs of rebuild_predicted_model also fail with the same result. Tried it with models and maps for different proteins, tried both on Linux and Windows - it gives the same output (Phenix 1.20.1.-4487). Please, find the log attached. I am seeking for any advice on resolving this problem. Best regards Andrey Moiseenko Electron Microscopy Lab @ Biology Department Moscow State University <mailto:[email protected]> postmoiseenko(a)gmail.com skype: callmoiseenko

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custom planar restraints ?
by Guenter Fritz 30 May '22

30 May '22

Dear all, is it possible to define custom planar restraints, let's say atoms A,B,C,D from residue Z should stay in a plane. Best regards, Guenter

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Phenix user workshop at the ACA2022 in Portland
by Dorothee Liebschner 25 May '22

25 May '22

Dear Colleagues, The Phenix developers will be holding a day-long satellite workshop on July 29th, prior to the ACA meeting in Portland, Oregon. This Phenix user workshop will focus on using predicted models for crystallography and cryo-EM The format of the workshop will be demos of the use of Phenix programs combined with slides to explain the theory. We expect an interactive meeting where attendees can ask questions for the Phenix team to answer. Topics will cover aspects of macromolecular structure determination in Phenix. For registration, see the ACA 2022 website: https://www.acameeting.com/aca-wk2 . Lecturers: Pavel Afonine, Dorothee Liebschner, Billy Poon, Tom Terwilliger Looking forward to seeing you there! The Phenix team Detailed Program: 8:00 Welcome: Introduction to Phenix, Introduction to the GUI, set up Phenix 8:45 Overview -- Strategy for X-ray or Cryo-EM structure determination using AlphaFold models (lecture) 9:15 Predicting your structure with AlphaFold and trimming it with ProcessPredictedModel (demo) 9:45 Solving an X-ray structure automatically by MR with PredictAndBuild (demo with pre-computed data) 10:15 Break 10:45 Evaluating X-ray data with Xtriage 11:00 Xray refinement (lecture) 11:30 Xray refinement with AlphaFold reference models (demo) 12:00 Lunch 13:00 Ligands (lecture & demo) 13:30 Cryo-EM Data evaluation with Mtriage (short lecture & demo) 13:45 Cryo-EM map manipulations, map improvement with LocalAnisoSharpen and ResolveCryoEM (demo) 14:30 Break 15:00 Automatic cryo-EM map interpretation with PredictAndBuild (demo with pre-computed data) 15:30 Cryo-EM refinement (lecture and demo) 16:00 Model validation (lecture & demo) 16:30 Q&A 16:50 finish: workshop survey and wrap up -- Research Scientist, Molecular Biophysics and Integrated Bioimaging Lawrence Berkeley National Laboratory 1 Cyclotron Road, M/S 33R0345 Berkeley, CA 94720 Tel: (510) 486-5709 Fax: (510) 486-5909 Web: https://phenix-online.org

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Exciting post-doc position available on DNA transcription and conjugation at the ALBA synchrotron
by Roeland Boer 17 May '22

17 May '22

Dear fellow structural biologists, I would appreciate it if you could forward this message to anyone that might be interested. We are looking for an enthusiastic and motivated early-career postdoc to study the structural aspects of auxin-dependent transcription regulation in plants, and/or plasmid conjugation in gram-positive bacteria at the ALBA synchrotron (Barcelona, Spain). The project is a continuation of the research lines of a highly successful research group, including publications in Cell (10.1016/j.cell.2013.12.027), Nature Communications (10.1038/s41467-020-16032-y), Nucleic Acids Research (10.1093/nar/gkaa540 and 10.1093/nar/gky996), Nature Plants (10.1038/s41477-020-0662-y) and PNAS (10.1073/pnas.2009554117). At the ALBA synchrotron, exciting times lie ahead for structural biologists. Recently, a new EM facility has been built and is being commissioned at the moment. In addition, an upgrade of the storage ring will come to fruition in the coming 5-10 years. Furthermore, a microfocus beamline is under construction that will be open to friendly users in the year to come. These instruments will complement the macromolecular crystallography, SAXS, infrared microscopy and X-ray microscopy beamlines currently in operation. The facility is located near Barcelona, which is a great city to live and work. For inquiries, please contact me at rboer(a)cells.es. To apply, please check the following page: https://public.cells.es/jobs/#!/jobs/postdoctoral-researcher-position-minec… Best, Roeland. -- <https://www.albasynchrotron.es/en/> Roeland Boer XALOC beamline- Experiments Division ALBA SYNCHROTRON LIGHT SOURCE Carrer de la Llum 2-26 | 08290 | Cerdanyola del Vallès| Barcelona | Spain <https://www.albasynchrotron.es/en/about/coming-to-alba> (+34) 93 592 4333 www.albasynchrotron.es <http://www.albasynchrotron.es>| rboer(a)cells.es <mailto:[email protected]> | legal notice <https://www.albasynchrotron.es/en/about/legal-notice> / avís legal <https://www.sincrotroalba.cat/ca/que-es-alba/avis-legal> / aviso legal <https://www.sincrotronalba.es/es/que-es-alba/aviso-legal> **Please, do not print this e-mail unless it is absolutely necessary. **Si heu rebut aquest correu per error, us informo que pot contenir informació confidencial i privada i que està prohibit el seu ús. Us agrairíem que ho comuniqueu al remitent i l'elimineu. Gràcies. Si ha recibido este correo por error, le informo de que puede contener información confidencial y privada y que está prohibido su uso. Le agradeceré que lo comunique a su remitente y lo elimine. Gracias. If you have received this e-mail in error, please note that it may contain confidential and private information, therefore, the use of this information is strictly forbidden. Please inform the sender of the error and delete the information received. Thank you.

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problem in cif file from Real-space refinement
by princeadam＠163.com 14 May '22

14 May '22

Dear all, I used the "Get PDB validation report"to refine my protein-ligand complex. The cif file got from "Get PDB validation report" was put into "Prepare model for PDB depositon" and then I used "Get PDB validation report" to see the validation report. It's a pity I got the following error message from "Get PDB validation report": The PDB server reports a failure with you data. Please check that your input files following the CIF specifications. However, if I use the cif file from phenix.refine with the same procedure, I got the validation reports normally. Does anyone has similar problem? I am using Phenix 1.20.1-4487. Thanks a lot for the help. Best Liu

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problem in cif file from Real-space refinement
by princeadam＠163.com 14 May '22

14 May '22

Dear all, Sorry, I made a mistake in the former email. I used the "real space refinement"to refine my protein-ligand complex. The cif file got from "real space refinement" was put into "Prepare model for PDB depositon" and then I used "Get PDB validation report" to see the validation report. It's a pity I got the following error message from "Get PDB validation report": The PDB server reports a failure with you data. Please check that your input files following the CIF specifications. However, if I use the cif file from phenix.refine with the same procedure, I got the validation reports normally. Does anyone has similar problem? I am using Phenix 1.20.1-4487. Thanks a lot for the help. Best Liu

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Error during phenix refine
by Shisler, Krista 12 May '22

12 May '22

Dear All, I ran Phaser-MR on my data (which I analyzed with xds) and was able to obtain a model with an TFZ score of 10.8. However, when I try to refine, I am getting an error message saying "cctbx Error: merge_equivalents_exact: incompatible flags for hkl = (-71, 39, 62) (mismatch between Friedel mates)." Is there a way to edit these flags or do I need to analyze my data again? Thank you! Krista

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TLS refinement and interpretation of the B factors
by 向嵩 10 May '22

10 May '22

Dear Phenix users, I have sent this message to phenixbb before I subscribed to it and did not see it show up in the bulletin board. I am sending it again and apologize for the possible duplicated messages. I have been trying to understand the B factors generated by TLS refinements and appreciate any help in this subject. In my particular case, I was trying to analyze the dynamics of different portions of a protein molecule by looking at the B factors. The structure was refined with the isotropic B factor and TLS and the TLS groups were determined automatically. After the refinement, I tried to analyze the TLS matrices with phenix.tls_analysis. The analysis failed for many of the TLS groups, the program complains that some of the matrices are not positive semidefinite. I have several questions related to this: 1, in cases like this, can I tweak the initial values of the matrix elements or add constrains to make the TLS refinement results physically meaningful? i.e. the refined TLS matrices can be interpreted in terms of elemental motions. I noticed that Afonine et al mentioned in a recent paper (doi: 10.1107/S2059798318005764) that a large fractions of TLS matrices in the PDB databank can not be interpreted by elemental motions. I wonder if there is a way to make the refined matrices more meaningful in the current implementation of TLS refinement in phenix? 2, what is the "best" B-factor to look at in an analysis for protein dynamics? I am interested in the dynamics of portions of protein that are smaller than the TLS groups. I am guessing that if the TLS matrices are not physically meaningful, one should look at the overall B-factors? If these matrices are meaningful, is it a good practice to look at the residual B factors (overall B-factor minus the TLS contributions)? 3, how to calculate the residual B factors? I could not find a manual for phenix.tls mentioned in the phenix refinement instruction. I tried with the extract_tls=true option with my PDB and got a PDB file with some negative B factors. Is it another sign that the refined TLS matrices are not physically meaningful or am I using the phenix.tls program wrong? Your help in this subject is greatly appreciated. Song Xiang

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Diffraction Methods in Structural Biology - Gordon Research Conference - July 24-29, 2022
by James Holton 07 May '22

07 May '22

Many of you may recall approximately 1000 years ago we were looking forward to getting together for another great Diffraction Methods GRC. Now, after a 4-year break, the meeting is on! https://www.grc.org/diffraction-methods-in-structural-biology-conference/20… It will be in-person at Bates College in Lewiston, ME, USA, on July 24-29 of 2022. Strange how it is strange to be considering meeting in person, but recent GRCs have proven they can be conducted safely. We've learned a lot about viruses in recent years, both in our lives and in our labs. Artificial Intelligence has come a long way, and the role of biological structure, and indeed science in general, is impacting the everyday lives of human beings more than ever before. It is time we got together to talk about all this. Yes, we've gotten a lot of work done remotely, but some things just have to wait until you are face-to-face. Preferably over a Maine lobster dinner. GRCs are not about listening to talks, they are about the discussion that comes after. Newcomers and Veterans sharing and debating ideas until far too late at night. It is my sincere hope that fighting this virus, and looking toward a brighter future, will inspire even more visionary and collaborative ideas for the role structure will play in that future. I can't imagine a better theme of discussion for this next meeting. Some may also recall that in 2020 we were accepting tax-deductible donations to help attendees from underrepresented groups overcome the financial barriers to GRC attendance. Those funds are still available, and donations are also still possible. I ask that applicants who feel they may qualify please self-identify to me, off-list, in an email. It is my goal to bring as many diverse backgrounds and points of view as possible into this meeting, because that is what makes for the most productive discussions. -James Holton MAD Scientist -James Holton MAD Scientist and Chair of the 2020/2022 Diffraction Methods GRC

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get list of missing atoms table in validation
by Wei Wang 05 May '22

05 May '22

Dear all, I would like to get an externally readable list of the missing atoms table in “Summary" session of "Comprehensive validation (X-ray/Neutron)". Currently it seems the information is integrated and clickable only inside the gui window. I want to access the table via sed. Is there a way to extract that table out? Best regards, Wei

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2022 Cold Spring Harbor Macromolecular Crystallography Course
by Paul Adams 04 May '22

04 May '22

Dear Colleagues, The July 15th deadline for applications to the CSHL Macromolecular Crystallography Course to be held later this year, October 10 through October 25 2022, is rapidly approaching. This is a unique opportunity to become expert in the use of crystallography to solve challenging macromolecular structures. The official course announcement can be found here: https://meetings.cshl.edu/courses.aspx?course=C-CRYS&year=22 please pass this on to anyone who you think might be interested and would benefit, especially students and postdocs. This comprehensive course is an outstanding place to learn both the theoretical and practical aspects of macromolecular crystallography, and consists of extensive lectures and practical sessions from experts in the field. The instructor team is: Janet Newman, Tom Peat, Jim Pflugrath, Tassos Perrakis, and myself. We are assisted by world recognized experts in crystallization, data collection, data processing, structure solution, refinement, and validation (see the course link above for more details). The goal of the course is for researchers who have had some exposure to structural biology to become experts in crystallography. This is an experience in macromolecular crystallography learning that cannot be found anywhere else, and the student/teacher ratio is often 1:1. We expect participants to crystallize one or more proteins and determine their structures in a two week period. Students may also work on their own projects, but not exclusively. They will become very well-versed in the theory of diffraction and crystal structure determination, while also having lots of fun. Both synchrotron data collection and in-house diffraction data collection will be used to solve structures. The course will also include the use of computationally predicted structures to aid in solving the crystallographic phase problem. The course is limited to 16 participants due to the very hands-on nature of the experiments and the intimate seminar and laboratory settings. Please check the above web link for more details. In particular, please note the information about the various fellowships, scholarships, and stipends that are available. The course is supported with funds provided by the National Institute of General Medical Sciences, for which we are extremely grateful. Also there are stipends available from the Leona M. and Harry B. Helmsley Charitable Trust and the Howard Hughes Medical Institute to help offset the cost of tuition. Scholarship support is also provided by Regeneron Pharmaceuticals. If anyone has any questions, please send me an e-mail, we will be happy to answer all queries. -- Paul Adams (he/him/his) Associate Laboratory Director for Biosciences, LBL (https://biosciences.lbl.gov/leadership/) Principal Investigator, Computational Crystallography Initiative, LBL (https://cci.lbl.gov) Vice President for Technology, the Joint BioEnergy Institute (http://www.jbei.org) Principal Investigator, ALS-ENABLE, Advanced Light Source (https://als-enable.lbl.gov) Division Deputy for Biosciences, Advanced Light Source (https://als.lbl.gov) Laboratory Research Manager, ENIGMA Science Focus Area (http://enigma.lbl.gov) Adjunct Professor, Department of Bioengineering, UC Berkeley (http://bioeng.berkeley.edu) Member of the Graduate Group in Comparative Biochemistry, UC Berkeley (http://compbiochem.berkeley.edu) Building 33, Room 250 Building 978, Room 4126 Building 977, Room 268 Tel: 1-510-486-4225 http://cci.lbl.gov/paul ORCID: 0000-0001-9333-8219 Lawrence Berkeley Laboratory 1 Cyclotron Road BLDG 33R0345 Berkeley, CA 94720, USA. Executive Assistant: Michael Espinosa [ MEEspinosa(a)lbl.gov ] [ 1-510-333-6788 ] Phenix Consortium: Ashley Dawn [ AshleyDawn(a)lbl.gov ][ 1-510-486-5455 ] --

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Phenix/Coot issue
by Xavier Brazzolotto 30 Apr '22

30 Apr '22

Dear Phenix and Coot users and developers I've recently observed a kind of conflict between Phenix and Coot. I am using Phenix v1.20.1-4487 and Coot 0.9.8.1 from thee CCP4 8.0 suite under macOS Monterey (v12.3.1). If I launch Coot through Phenix via the « Open in Coot » of a refine job for example (the path to Coot has been defined in Phenix preferences), Coot opens correctly and displays the structure with the « Connected to Phenix tab". However if I wand to do some RSR then I get an error message stating "Refinement setup failure » : « Failed to find restraints for » and a list of the residues involved in RSR. In parallel if I use Coot by itself (launched through the terminal), RSR works well… but upon opening Coot states that there is some "Nomenclature errors » with a list of different residues. I wonder if there would be some conflict between residue libraries between Phenix and Coot ? Just to leet you know I’ve also recently tried to install/comlplie the Coot v1 pre-version to have a loot at it and I do also have libccp4 installed in my Homebrew. Maybe everything comes from that ? Xavier

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3Fe4S clusters in real-space refinement
by Rhys Grinter 28 Apr '22

28 Apr '22

Hi PHENIX BB, I'm currently refining a structure with 3Fe4S clusters into some high resolution cryoEM maps (1.57 Ang). However, refinement messes up the Fe4S cluster, by moving the existing Fe and S atoms into the wrong positions in the density. Is anyone aware of this issue and/or knows of a simple way to prevent this from happening? Cheers, Rhys -- Dr Rhys Grinter Lab Head Molecular Physiology of Microbial Pathogens (MP2) Lab Monash University +61 (0)3 9902 9213 +61 (0)403 896 767

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Re: [phenixbb] NaN of AlphaFold
by Randy John Read 26 Apr '22

26 Apr '22

Did you try looking at a surface representation of the structure? The one that Pavel generated from a more simplistic random sequence looked vaguely plausible as a chain trace, but had very large cavities when viewed as accessible surface, e.g. in ChimeraX. Randy > On 24 Apr 2022, at 01:36, James Holton <jmholton(a)lbl.gov> wrote: > > I downloaded all sequences from the PDB to do a frequency analysis, which I think will enable a more sophisticated "random peptide" than giving all 20 amino acids equal likelihood with no neighbor correlations. Turns out the most common heptapeptide in the PDB is: > XXXXXXX > > because, apparently, NCBI lists gaps like this. If I eliminate "X", the most common heptapeptide is: > > SHHHHHH > > Right. His tags. If I eliminate those, the next one is: > GLVPRGS > thrombin cleavage site. Ugh! > > Cleaving off those, the next one is: > AAAAAAA > apparently also used to denote unknown amino acids. > > Ignoring those, the next one is: > YFPEPVT > this is from the human antibody heavy chain. Thousands of those in the PDB. This made me realize that there is going to be a lot of "homology bias". > > I next tried the NCBI refseq_select to try and get something non-redundant, and then I get: > GSGKSTL > lots of ABC transporters. >10k of this sequence in the db. > > On the other hand, of the ~330e6 heptapeptide sequences I'm looking at, 52% of them only appear once. Another 19% of my list of unique sequences occur twice, 9% occur 3x, etc. It is a VERY steep curve. Only 4% of my sample sequences occur more than 10 times, and 0.05% occur more than 100x. I never thought of the PDB this way, but I take this as indicative of how much repetition there is in the sampling. Perhaps I need to brush up on my statistics, but I did not expect this. > > So, I said "heck with it" and simply extracted all heptads that only occur EXACTLY ONCE in the PDB. There are 7.4e6 of them. I chose one at random as the starting 7 residues: FLACISE (from 6ekr). Rather than simply appending random heptads, I took the final ISE and extracted all one-off heptads that begin with ISE. There are 1905 of those. I chose one at random: ISENDGN (from 6ixy). I then extracted heptads beginning with DGN, etc. Final sequence of randomly-assembled yet abbuting heptads from random places in the PDB is then: > > > random1 > FLACISENDGNDGDKSNLAQDTDLALGTWVRDISIALRSGFIAEEYPAWWKESVVPYYNQLNGN > DIEHSHSALLPTGIYFLEIPLVGTRDVALDTEGETTEEAFRHLDGIVGHPIVIGRRAADGGPLVIRGL > NEVLLRLSEVYNAWKLLKVQEILKGLEAYNRAMDYETILREGTWKPAGYTPNALAGGAQCGNAD > IVNERIISDGVEASQLATLERRENRALQTALEIENGELEQKWGRLPSAXPAVERQRYRGPSTATW > EGFSTDGRFPSEVDIFDRETLDGVEGLAKDVEALKGVLMGLFAPYWKWCTHNCIGYAARFVALN > KAIRTALTFARTHSNNETIHNEVVGMIPDIDIAVSDINSQEYTKTRSERQGGVLKEHLNALNAKIEPS > VNLKVSA > > A quick BLASTP shows a surprisingly high homology match: > <o4TgiNP8vaFOcUkl.png> > > I mean... not great, but higher than I'd expect for "completely random" ? > > > The alphafold2 colab result looks like this: > > > <rHffn0Fa0WfwR4Yg.png> > > So still lots of helical content. This shape makes me want to make this sequence and see if it folds. It probably doesn't. But if this thing weren't red I'd wonder. > > Discuss? > > -James > ----- Randy J. Read Department of Haematology, University of Cambridge Cambridge Institute for Medical Research Tel: +44 1223 336500 The Keith Peters Building Fax: +44 1223 336827 Hills Road E-mail: rjr27(a)cam.ac.uk Cambridge CB2 0XY, U.K. www-structmed.cimr.cam.ac.uk

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Refining cyclosporin A
by Armando Albert 22 Apr '22

22 Apr '22

Dear All, We are trying to refine a protein complex with cyclosporin which is a non conventional cyclic peptide. I wonder what is the best strategy to build the cif file. Shall we define the cif file for individual non-conventional amino acids and then link them or shall we define the whole structure as an individual ligand? Does any one have the corresponding cif file? Armando

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Validation of structure with modified residue
by Xavier Brazzolotto 21 Apr '22

21 Apr '22

Dear Phenix users, I don’t know if my problem is related to Phenix but for information I’m running Phenix 1.20.1-4487 under MacOS 12.3.1. I’ve finalized a structure where a ligand covalently modified the protein. I’ve generated the modified residue (named SLG for serine modified by ligand). For this I’ve generated the molecules in SMILES and used eLBOW to generate the restraints. Then I’ve modified the cif file defining the molecule as a L-peptide and replacing the atom names of the Serine part (CA, CB, OG, C, O, N, and OXT) In coot (from CCP4 : 0.9.6 EL), I’ve used the modified cif file and it allowed merging of the modified residue into the polypeptide chain as expected and further refinements went without any issue in Phenix (providing the modified cif file of course). Everything seems well interpreted. So far so good. However, now I would like to validate the structure and both Phenix validation tool and the PDB web server do not accept the final cif file. Checking this file I’ve noticed that the protein seems split into 3 pieces (chain A, first residue up to the one before the modified residue; chain B the modified residue by itself described as HETATM and chain C the rest of the polypeptide up to the C-ter). The PDB file presents only one chain A for the whole protein with the modified residue... I don’t know if this is an issue with Phenix generating this final cif file in this specific case or if I need to modify this final file by hand ? Any help is welcome. Thanks Xavier

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ligand at two-fold
by Patrick Loll 14 Apr '22

14 Apr '22

Hello all, I have a dimer in which the two protomers are related by a crystallographic 2-fold. There is a peptide ligand that sits in the interface between the two protomers. This means that the ligand will be present in two orientations, and I’ve set the occupancies to 0.5. However, the ligand is pushed out of density during refinement, presumably because orientation #1 is repelling orientation #2 (to be clear, orientations #1 and #2 are symmetry mates). To deal with this, I include a parameter file in the GUI that contains the following instruction: custom_nonbonded_symmetry_exclusions = "chain X” [where chain X is the peptide ligand] However, the refinement fails, with the following error message: "Unused parameter definitions: Please check the input file(s) for spelling errors and obsolete parameter definitions." This would seem to imply that the custom_nonbonded_symmetry_exclusions command is obsolete, but it’s still found in the list of all available keywords (?). Any help would be welcome. Thanks, Pat --------------------------------------------------------------------------------------- Patrick J. Loll, Ph. D. (he, him, his) Professor of Biochemistry & Molecular Biology Drexel University College of Medicine Room 10-102 New College Building 245 N. 15th St., Mailstop 497 Philadelphia, PA 19102 USA pjl28(a)drexel.edu pjloll(a)gmail.com

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Error from exceeding max reasonable bond distance
by Mullins, Elwood A. 13 Apr '22

13 Apr '22

I’m having an issue with a real-space refinement job crashing after giving the following error: "RuntimeError : Bond distance > max_reasonable_bond_distance: 62.8014 > 50". I found mention of this problem in a post from 2017. I tried the recommended solution (setting the max reasonable bond distance to 999), but that caused the job to hang. I also tried clicking “proceed with excessive length bonds”. That didn’t make a difference; I received the same error message. I ran validation on the model. There are no bond length outliers and only minor other issues. Any help would be greatly appreciated. Thanks, Elwood

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The lowest resolution score X-ray statics resolution bin is lower than overall datasets.
by Takebe Katsuki 11 Apr '22

11 Apr '22

Dear all, I am working on a 20 KD protein and We scaled the data sets 1.6Å. The lowest resolution score X-ray statics resolution bin is lower than overall datasets. Is this seriously problem? and How do I solve the problem? Could you give me some advice on this problem? DATA USED IN REFINEMENT. RESOLUTION RANGE HIGH (ANGSTROMS) : 1.600 RESOLUTION RANGE LOW (ANGSTROMS) : 44.488 　 [cid:[email protected]]

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2022 ACA session on AI predicted Models in Structural Biology/Crystallography
by Aaron Brewster 11 Apr '22

11 Apr '22

Hi all, we'd like to call your attention to the upcoming session at the 2022 ACA on the use of AI predicted Models in Structural Biology/Crystallography. We'd like to invite abstract submissions to this session from people, including early-career scientists, who have done difficult or interesting work using these AI predicted structural models, such as from AlphaFold2 and RoseTTAFold. We are very excited to hear what people are using these tools for and how the future might unfold in this new world of AI-aided structural analysis and design. Remember that the deadline to submit an abstract for talks is April 15, 2022@ 11:59 PM ET. The full abstract for the session is below. Thanks, -Aaron Brewster and John Moult Prediction of 3D protein structure by AlphaFold2 and RoseTTAFold has achieved revolutionary accuracy using new AI methods. These programs can accurately predict the 3D structure of many proteins from 1D amino acid sequences, opening up a vast array of exciting new experiments and challenges for researchers. In this session we will explore current applications of these structures in molecular replacement, cryo-EM fitting and refinement, structure-based drug design, and tomography. We will explore what kinds of new and difficult methods have been enabled and what remains difficult. Other topics may include how error estimates on AI protein models can be incorporated into these methods, progress in modeling of protein complexes, implications of AI structures on protein design, the generation and use of structure ensembles, and new data analysis best practices that need to be developed as the use of computer-generated structures becomes more common. Sponsored by the BioMAC and Best Practices for Data Analysis and Archiving SIGs

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The lowest resolution score X-ray statics resolution bin is lower than overall datasets.
by Takebe Katsuki 11 Apr '22

11 Apr '22

Dear all, I am working on a 20 KD protein and We scaled the data sets 1.6Å. The lowest resolution score X-ray statics resolution bin is lower than overall datasets. Is this seriously problem? and How do I solve the problem? Could you give me some advice on this problem? DATA USED IN REFINEMENT. RESOLUTION RANGE HIGH (ANGSTROMS) : 1.600 RESOLUTION RANGE LOW (ANGSTROMS) : 44.488 　 [cid:[email protected]]

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Fragment-based drug discovery session at ACA 2022
by Tanner, John J. 08 Apr '22

08 Apr '22

As many of you know, the 2022 ACA meeting will be held in Portland, OR on July 29 to August 2. I would like to draw your attention to the session on fragment-based drug discovery and invite you to submit an abstract for an oral presentation. We welcome contributions from students as well as PIs. The Abstract deadline is April 15. https://www.acameeting.com/ Session details: 3.2.2 Fragment Based Drug Discovery 8/1/2022 @ 2:00:00 PM - 5:00:00 PM Sponsoring SIG(s): Industrial Co-Sponsoring SIG(s): BioMac Session Chair(s): Matt Clifton, Jack Tanner Fragment Based Drug Discovery (FBDD) utilizes small molecule compounds to help identify starting points in the drug discovery process. This process allowed for the discovery of lead compounds for difficult protein targets with small/shallow pockets or protein-protein interactions. In contrast to other screening techniques such as High-Throughput Screening (HTS) or DNA-encoded Libraries (DEL), FBDD utilizes small libraries of molecules (< 2000) with molecular weights less than ~200 Da. FBDD has been key in the development of multiple approved drugs and dozens of other drugs in clinical trials. This session will focus on the biophysical and structural techniques used in FBDD to identify initial starting points, optimization by fragment growing/linking, and the route to lead optimization. -- John J. Tanner Professor of Biochemistry and Chemistry Associate Chair of Biochemistry Department of Biochemistry University of Missouri 117 Schweitzer Hall 503 S College Avenue Columbia, MO 65211 Phone: 573-884-1280 Email: tannerjj(a)missouri.edu<mailto:[email protected]> https://cafnrfaculty.missouri.edu/tannerlab/ Lab: Schlundt Annex rooms 3,6,9, 203B, 203C Office: Schlundt Annex 203A

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CCN submissions and current issue
by Nigel Moriarty 05 Apr '22

05 Apr '22

Folks The deadline for submissions to the Computational Crystallography Newsletter (CCN) is 1 JUN 2022. Please consider writing an article of general interest to the community. The Computational Crystallography Newsletter (CCN) is an electronic newsletter for structural biologists, and is published online every 6 months. Feature articles, meeting announcements and reports can be submitted to me at any time for consideration. Submission of text by email or word-processing files using the CCN templates is requested. Past newsletters and a Microsoft Word template is attached to this email. Current Issue: January 2022 Full issue <https://phenix-online.org/phenixwebsite_static/mainsite/files/newsletter/CC…> Articles: - Extreme backbone outlier patterns when AlphaFold gives up <https://phenix-online.org/phenixwebsite_static/mainsite/files/newsletter/CC…> - Difference Density Tracer: A Tool for Rapid Visualization of Difference Densities in Proteins to identify Dynamics <https://phenix-online.org/phenixwebsite_static/mainsite/files/newsletter/CC…> Fitting Tips: - Fitting tips #22 – Places where you should never fit a cis-nonPro peptide <https://phenix-online.org/phenixwebsite_static/mainsite/files/newsletter/CC…> Cheers Nigel --- Nigel W. Moriarty Building 33R0349, Molecular Biophysics and Integrated Bioimaging Lawrence Berkeley National Laboratory Berkeley, CA 94720-8235 Phone : 510-486-5709 Email : NWMoriarty(a)LBL.gov Fax : 510-486-5909 Web : CCI.LBL.gov ORCID : orcid.org/0000-0001-8857-9464

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Question about RMSD vs e/A^3
by Vatsal Purohit 30 Mar '22

30 Mar '22

Hi all, I had a question about comparing structures based on RMSD comparisons vs e-/A^3. While the former seems to be more frequently used in structural studies with a standard value of 1.0 rmsd for 2Fo-Fc and 3.0 rmsd for Fo-Fc, there are differences in RMSD based on resolution. Hence, I wanted to ask if e-/A^3 could be a more appropriate comparison for looking at differences in electron density in a ligand-binding site between 2 structures of the same enzyme? So, here you would try and set e-/A^3 of all the maps (2Fo-Fc and Fo-Fc) to the same value. The structures I’m referring to are between 2-2.5 angstroms in resolution. I have also worked with the map sigma level comparison tool on PHENIX and wanted to know if that might be an alternate way to compare maps in 2 structures accordingly. Regards, Vatsal Post-doctoral fellow, Davis Lab, Emory University vatsal.purohit(a)emory.edu <mailto:[email protected]> | 346-719-9409

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