March 2023 - phenixbb - phenix-online.org

map deposition strategy after density modification
by Daniel Larsson 20 Sep '23

20 Sep '23

Hi Phenix community, I’ve been using density modification with some success for my data and am considering the most appropriate way to do model building/refinement and then deposition of my results. Here are some questions/observations: 1) Which map should I refine against (most importantly, do the final minimization using phenix.real_space_refine)? The DM map is the most clear one, so I’m favoring to do it against this one (as long as the geometry/validation is also best for this one). 2) Which map should I deposit as my main map? Is it the autosharpened one or the DM one? Since the DM map looks the best, I want the user who only downloads one map to see this one, so again I favoring this map. 3) Which nominal resolution should I quote for my reconstruction? Since the procedure seems to introduce correlation between the two maps (see point 4 below), it does not seem to be possible to obtain a gold-standard FSC value between two truly independent half-maps. As the DM procedure supposedly actually improves the map (by leveraging knowledge about what solvent and macromolecular maps usually looks like and thereby improves the Fourier coefficients), it feels like it would be misrepresenting the data by quoting the FSC_0.143 from the original reconstruction. Should I use the FSC_0.5 estimated value that phenix.resolve_cryo_em outputs? 4) Which FSC curve should I deposit? When I calculate the FSC between the two density modified half-maps, I get a funny (or rather not so funny) looking curve with a bump at around 3Å and it does not go to zero at Nyquist (which does not agree with the map quality). This must again be due to the induced correlation between the maps, presumably during the masking of solvent and macromolecule density. Phenix.resolve_cryo_em calculates a FSC curve to calculate the FSC_0.5 value, which according to the manual page corrects for the correlation induced between the two maps: "Density modification introduces some correlations between half-maps due to solvent flattening. This can have a small effect on the resolution estimates obtained with half-map FSC. The resolution estimates provided by the program are corrected for this effect." But is this curve good enough? I think OneDeposit wants to have the gold-standard FSC curve, right? 5) Which (nowadays mandatory) half-maps should one deposit? Here I would say that the original half-maps before DM makes more sense, since these are less processed. But if one specify these as the half-maps, there will be inconsistencies during validation, since the DM map will look quite different from the average between the two original half-maps. Also the automatic FSC curve will be very different from the deposited one. So in conclusion, despite what I say above, the most conservative thing would be to deposit the conventionally sharpened map as my main map and use the original half-maps for calculating the FSC-curve and use the 0.143 threshold from this curve to estimate the resolution. The DM map can be used during rebuilding/refinement, but I think final minimization should be against the main map during deposition (with restraints if the geometry gets worse). The DM map can be deposited as an auxiliary map. Do the community and the developers agree? 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

4 4

Virtual Crash Course - Understanding PDBx/mmCIF | May 3rd | REGISTER NOW!
by Chenghua Shao 02 May '23

02 May '23

*Use PDB data to their full extent: Understanding PDBx/mmCIF * Wednesday, May 3rd 2023 | 1:00 PM EDT Registration: go.rutgers.edu/u3vpwjet <https://go.rutgers.edu/u3vpwjet> * This RCSB Protein Data Bank (PDB) virtual course will be broadcast on Zoom. Please fill out the registration form to receive the Zoom link. Registration will be available online from March 1, 2023 to May 3, 2023. LEARNING OBJECTIVES Understand the basics of PDBx/mmCIF data dictionary and file format that underpin archiving of more than 200,000 experimentally determined three-dimensional biostructures in the PDB. Learn about software tools for generating and working with PDBx/mmCIF files, and programmatic access for harvesting PDB data. Main topics: * PDBx/mmCIF format description and examples * PDBx/mmCIF data model * Software tools for generating, editing, and visualizing PDBx/mmCIF files * PDBx/mmCIF dictionary extensions, including ModelCIF for computed structure models (CSM) from AI/ML * Parsing data from PDBx/mmCIF files for your research *WHO SHOULD ATTEND * Professionals and graduate students interested in learning about strategies to take full advantage of PDB data in the fields of: * Structural biology * Cheminformatics and computational chemistry * Bioinformatics and computational biology *PROGRAM* | Download Printable Program <https://iqb.rutgers.edu/sites/iqb.rutgers.edu/files/crashcourses/mmCIF-cras…> 1:00–1:10 PM Welcome Stephen K. Burley, M.D., D.Phil. Director, RCSB PDB and Founding Director, Institute for Quantitative Biomedicine, Rutgers University 1:10–1:25 PM Introduction and course objectives Gregg Crichlow, Ph.D., RCSB PDB, Rutgers University 1:25–1:45 PM PDBx/mmCIF format - Not your parents’ legacy PDB format Ezra Peisach, Ph.D., RCSB PDB, Rutgers University 1:45–2:05 PM PDBx/mmCIF data files - Lifting the lid off the black box Brian Hudson, Ph.D., RCSB PDB, Rutgers University 2:05–2:50 PM Programmatic data access and analysis using PDBx/mmCIF files Irina Persikova, Ph.D. and Chenghua Shao, Ph.D., RCSB PDB, Rutgers University 2:50–3:00 PM Closing remarks and acknowledgements Stephen K. Burley, M.D., D.Phil. Development and management of the PDBx/mmCIF data dictionary is a collaborative effort involving RCSB PDB, Worldwide Protein Data Bank (wwPDB, wwPDB.org <http://www.wwpdb.org/>) partners, and members of the wwPDB PDBx/mmCIF Working Group (wwpdb.org/task/mmcif <https://www.wwpdb.org/task/mmcif>). CO-ORGANIZERS RCSB PDB Biocurators: Gregg Crichlow, Justin Flatt, Sutapa Ghosh, Brian Hudson, Yuhe Liang, Ezra Peisach, Irina Persikova, Monica Sekharan, Chenghua Shao, Jasmine Young (Rutgers, The State University of New Jersey). *QUESTIONS* Contact Michelle Sanghera msanghera(a)iqb.rutgers.edu *CO-SPONSORS * ** RCSB Protein Data Bank rcsb.org <https://www.rcsb.org/> RCSB PDB is managed by Rutgers, UCSD/SDSC, and UCSF. RCSB PDB is supported by grants from the NSF (DBI-1832184), the US DoE (DE-SC0019749), and the NIH (R01GM133198). RCSB PDB is a founding member of the wwPDB. Institute for Quantitative Biomedicine iqb.rutgers.edu <https://iqb.rutgers.edu/>

1 2

restraints_edits.params -- inquiries -- issues
by p.auffinger 30 Mar '23

30 Mar '23

Hi phenix users, I started to add restraints to a large ribosomal file by using the file (in full) below. I encountered two issues: 1) The first one is: how to use this file in the GUI? It seems to get rejected while its accepted when I run phenix through the command line. 2) The second is: restraints involving water molecules with residue numbers > 9999 get rejected. Could that limit be overcome through a future patch? ### refinement.geometry_restraints.edits { MG_8078 = chain 0 and resname MG and resid 8078 and name MG W_12641 = chain 0 and resname HOH and resid 12641 and name O bond { action = *add atom_selection_1 = $MG_8078 atom_selection_2 = $W_12641 symmetry_operation = None distance_ideal = 2.2 sigma = 0.1 slack = None } } ### Thanks for any thoughts on this, Pascal ----- Pascal Auffinger IBMC/CNRS 15 rue René Descartes 67084 Strasbourg Cedex p.auffinger(a)ibmc-cnrs.unistra.fr -----

2 1

27th Annual SCSB Structural Biology Symposium - Registration NOW OPEN
by White, Mark 21 Mar '23

21 Mar '23

You and your colleagues are cordially invited to join us for the 27th Annual Structural Biology Symposium to be held on April 29, 2023 in Levin Hall, UTMB Galveston. The meeting is organized by the Sealy Center for Structural Biology & Molecular Biophysics and co-sponsored by the Keck Center for Computational & Structural Biology. This year’s speakers include: Yunfeng Chen Ph.D. Univ. of Texas Medical Branch Ruben L. Gonzalez Jr., Ph.D. Columbia University John A. Tainer, Ph.D. University of Texas MD Anderson Cancer Center David W. Taylor, Ph.D. University of Texas Junjie Zhang Ph.D. Texas A&M University To register or for more information, visit https://scsb.utmb.edu/symposium Mark Andrew White, Ph.D. Associate Professor of Biochemistry & Molecular Biology, UTMB, Galveston, TX 409.747.4747 https://xray.utmb.edu ________________________________

1 0

Save the date! “Not the GRC” on Diffraction Methods in Structural Biology 2024
by Winter, Graeme (DLSLtd,RAL,LSCI) 17 Mar '23

17 Mar '23

Good afternoon all, “Not the Gordon Research Conference” on Diffraction Methods in Structural Biology 2024 - Experiments and Measurements Organisers: Graeme Winter, Kunio Hirata (NTGRC-chairs) Helena Taberman, Ali Ebrahim (NTGRS-chairs) Local organisers - Arwen Pearson, Ashwin Chari As you will have seen from a message from James Holton last year, the GRC have decided that the 2024 meeting on Diffraction Methods will not be further supported. We are not deterred! A number of the GRC ex-chairs and those nominated for chairing the next meeting feel that this opportunity for the diffraction methods community to come together is important enough that it should continue to happen, even without GRC support. We are therefore delighted to launch the “Not-the-GRC Diffraction methods in Structural Biology”. The topic of the meeting will be “Experiments and Measurements” and we have a great lineup of speakers in mind. Where: https://www.harnackhaus-berlin.mpg.de/en When: 21st - 27th July 2024 i.e. about when the next diffraction methods meeting would have been. Starting with the model of the GRC, since we collectively believe it is a fantastic meeting, we plan to make a few improvements (better accommodation and acoustics, fewer minimum attendees to keep the feel of a small meeting) and we will keep the equivalent of the GRS before the main meeting, as well as the free afternoons for collaborative discussion, and the strong emphasis on being able to talk to everyone. We will also keep the focus on new ideas and so follow the protocol of not recording presentations and encouraging the presentation of unpublished data and ideas. With that in mind, this will be a small meeting (100-120 maximum) so there will be an application process and we will open registration in January 2024. We also want as many early career people as possible - the last GRC was refreshing and fun with a lot of new faces, and this is something we want to build on. So, please hold the date in your calendar and we look forward to sharing the scientific programme with you in the coming months and seeing many of you in Berlin next summer. All the best Graeme, Kunio, Helena, Ali, Arwen and Ashwin -- This e-mail and any attachments may contain confidential, copyright and or privileged material, and are for the use of the intended addressee only. If you are not the intended addressee or an authorised recipient of the addressee please notify us of receipt by returning the e-mail and do not use, copy, retain, distribute or disclose the information in or attached to the e-mail. Any opinions expressed within this e-mail are those of the individual and not necessarily of Diamond Light Source Ltd. Diamond Light Source Ltd. cannot guarantee that this e-mail or any attachments are free from viruses and we cannot accept liability for any damage which you may sustain as a result of software viruses which may be transmitted in or with the message. Diamond Light Source Limited (company no. 4375679). Registered in England and Wales with its registered office at Diamond House, Harwell Science and Innovation Campus, Didcot, Oxfordshire, OX11 0DE, United Kingdom

1 0

Postdoc positions in cryo-EM development at the MRC Laboratory of Molecular Biology, Cambridge UK
by Jan Löwe 13 Mar '23

13 Mar '23

*Postdoctoral positions available in cryo-EM methods development at the MRC Laboratory of Molecular Biology, Cambridge UK, in the groups of Chris Russo and Jan Löwe* We have one position each available, funded for two years as part of the LMB’s Blue Sky collaboration with AstraZeneca. The project, in collaboration with Kasim Sader at AZ aims to develop novel methods to overcome problems with sample denaturation and preferred orientation during vitrification of thin aqueous films. Ideas involve outrunning the processes involved and modifying the air-water interfaces. The ultimate goal is to make cryo-EM sample preparation a much more universal (and enjoyable) process. Cryo-EM experience will be beneficial and a strong desire to engage deeply in technical developments is a must. The LMB and AZ provide everything required, including a highly collaborative and friendly environment, as well as one of the world’s best institutional cryo-EM setups, including state-of-the-art machine and electronics workshops, a clean room dedicated to grid fabrication, and soon four Titan Krios microscopes. More details and on how to apply are here: https://www.nature.com/naturecareers/job/12796284/postdoctoral-scientist-st… https://www.nature.com/naturecareers/job/12796280/postdoctoral-scientist-st… Chris, Kasim and Jan Jan Löwe MRC Laboratory of Molecular Biology, Cambridge CB2 0QH, UK Email: jyl(a)mrc-lmb.cam.ac.uk Phone +44 1223 26 7644 Website: http://www2.mrc-lmb.cam.ac.uk/groups/jyl Christopher J Russo  MRC Laboratory of Molecular Biology  Cambridge, CB2 0QH, UK Email: crusso(a)mrc-lmb.cam.ac.uk  Phone +44 1223 26 7535 Website http://www.mrc-lmb.cam.ac.uk/crusso/

1 0

Local restraints
by Luca Pellegrini 07 Mar '23

07 Mar '23

How can I freeze a set of atoms in phenix.real_space_refine? I've got an arginine side chain that is consistently misplaced during refinement, and I’d like to restrain its movement. I notice that refinement.geometry_restraints.edits.scale_restraints is not available anymore, is there another way? Thanks, Luca Luca Pellegrini, PhD Department of Biochemistry University of Cambridge Cambridge CB2 1GA UK

2 3