- phenixbb - phenix-online.org

project directories
by Arthur Glasfeld 08 Sep '20

08 Sep '20

I’ve changed computers recently and for administrative reasons had to change my userID. As a result, all of the directories containing my phenix projects have changed. Is there a simple way to update the directories associated each project? Thanks Arthur ***************** Arthur Glasfeld Reed College Portland, OR 97202

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group on special position
by Arthur Glasfeld 04 Sep '20

04 Sep '20

I’ve run into a situation where I think I have a phosphate sitting on a 3-fold axis, where the P to O1 bond lies on the axis and the atoms O2, O3 and O4 are in symmetry-related positions. The data go to 1.6 Å, so it looks pretty convincing. I’m refining this in Phenix and have tried some tricks with occupancy - fixing the atoms at 0.33, but I get a lot of positive density in the Fo-Fc map and large B-factors. I’ve looked around but am not finding ideas on how to model this correctly in my structure file - the references I find are for monoatomic ions. Any advice would be welcome. Thanks, Arthur ***************** Arthur Glasfeld Reed College Portland, OR 97202 Office: (503)517-7679

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General interest re research data
by John R Helliwell 01 Sep '20

01 Sep '20

Dear Colleagues, A couple of research data matters that I imagine will be of general interest I have placed at the IUCr CommDat Forum:- The Photon and Neutron EU Facilities Open Science Cloud announced their “doi per experiment” described in this 3 minutes youtube movie clip https://forums.iucr.org/viewtopic.php?f=39&t=431 Secondly, the Swiss Universities Bulletin have produced a special issue on Research Data Management, to which I have contributed an article on Open science and the reproducibility of the scientific record https://forums.iucr.org/viewtopic.php?f=39&t=432 Best wishes, John Emeritus Professor John R Helliwell DSc Chairman of the IUCr Committee on Data

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Phenix User Workshop, 15th and 16th of September
by Paul Adams 31 Aug '20

31 Aug '20

Dear Colleagues, The Phenix developers will be holding an online Phenix User Workshop on the 15th and 16th of September at 8am-12pm PDT. These times will work best for researchers in North and South America, Europe and Africa. We plan to hold a future workshop at a time better suited to researchers in Asia and Australasia. 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. The workshop will cover aspects of crystallography and cryo-EM in Phenix, with the final emphasis based on the applicants’ research interests. To apply, send email to workshops(a)phenix-online.org with a short paragraph about your interests. We will make every effort to accommodate all applicants, but may need to defer some requests to a future workshop if demand is high. We are hoping this workshop will be a success, in which case we plan to host more in the future. Cheers, The Phenix Developer Team -- Paul Adams Division Director, Molecular Biophysics & Integrated Bioimaging, LBL (http://biosciences.lbl.gov/divisions/mbib) Principal Investigator, Computational Crystallography Initiative, LBL (http://cci.lbl.gov) Vice President for Technology, the Joint BioEnergy Institute (http://www.jbei.org) Principal Investigator, ALS-ENABLE, Advanced Light Source (http://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, U.C. Berkeley (http://bioeng.berkeley.edu) Adjunct Professor, Comparative Biochemistry, U.C. Berkeley (http://compbiochem.berkeley.edu) Building 33, Room 250 Building 978, Room 4126 Building 977, Room 180C Tel: 1-510-486-4225 http://cci.lbl.gov/paul Lawrence Berkeley Laboratory 1 Cyclotron Road BLDG 33R0345 Berkeley, CA 94720, USA. Executive Assistant: Ashley Dawn [ ashleydawn(a)lbl.gov ][ 1-510-486-5455 ] --

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phenix.resolve_cryo_em
by Reza Khayat 25 Aug '20

25 Aug '20

?Hi, I'm running into a clipping issue with phenix.resolve_cryo_em. The program seems to be improving the map; however, portions of the map get clipped. Any suggestion would be appreciated. Best wishes, Reza Reza Khayat, PhD Associate Professor City College of New York Department of Chemistry and Biochemistry New York, NY 10031

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MicroED Imaging Center
by Johan Hattne 24 Aug '20

24 Aug '20

Dear Structural biology community; We are delighted to announce that the National Institutes of Health is helping us establish a Biotechnology Development Research Center focused on MicroED at UCLA School of Medicine, named MicroED Imaging Center (MEDIC). The main thrust of MEDIC is for method development and research focused on MicroED. As part of community engagement, the center will host the annual MicroED course as well as an annual MicroED Summit, both of which will be staged at the UCLA School of Medicine, and open to the community on a first come first serve basis until spaces are filled. Approximately 90% of available spots will be allocated to academic attendees and 10% to industry attendees. This will be a continuation of almost 10 years of tradition of providing workshops and training to the community. Also, there is some opportunity for the community to collect data on MEDIC microscopes. There is also limited availability for one-on-one user training at the center at UCLA for microscope set up and data collection. Users and trainees will be invited based on replies to a call for proposals, which will be advertised shortly. The proposals will be reviewed by an advisory committee. Because of the COVID19 pandemic and the limitations on travel and hosting imposed by UCLA we cannot begin these activities at this stage. On a related note, UCLA School of Medicine is also running a MicroED Imaging Core which is open as a pay per use service for academia and industry. This activity is independent of the Gonen Lab and from the NIH funded research program on MicroED. Details can be found online. Kind regards Tamir Gonen and Pawel Penczek

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error while Auto sharpen
by sangeeta niranjan 19 Aug '20

19 Aug '20

Hello, I am trying to use Auto Sharpen feature of a CyoEM refined map into Phenix but the job is getting failed every time with the following error: Missing the model file: followed with model file name and location. Although it was working before but now it's showing the same error for all the auto sharpen runs including Models/PDBs. Thank you -- Sangeeta Niranjan Ph.D. Student, Lab of structural Biology Lab-6 NB National Centre for cell Science Ganeshkhind, Pune, India

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moving folders
by Thomas, Leonard M. 18 Aug '20

18 Aug '20

Hello, I know this come up every so often by my google-fu is sorely lacking to find the answer. How does one move a project folder? I have a project and not thinking things through set it up in the wrong folder. I would like to move the whole thing to another folder maintaining the project structure. Thanks, Len Leonard Thomas, Ph.D. Macromolecular Crystallography Laboratory Oklahoma COBRE in Structural Biology Price Family Foundation Institute of Structural Biology University of Oklahoma Department of Chemistry and Biochemistry Stephenson Life Sciences Research Center 101 Stephenson Parkway Norman, OK 73019-5251 Office: (405)325-1126 lmthomas(a)ou.edu<mailto:[email protected]> http://www.ou.edu/structuralbiology/cobre-core-facilities/mcl

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Phenix.Refine fix WXC has no effect
by White, Mark 17 Aug '20

17 Aug '20

Hello, I am refining a 3.5 Å structure using the latest stable version of Phenix.Refine. After switching to the latest version the Bond RMSDs exploded to ~ 0.035 Å, when using optimize wxc. Turning off Optimize and using the "Fix WXC" parameters in the GUI with increasingly smaller values had almost no effect on the final bond rmsds, which seems to explode from reasonable values in the "3_xyz" step of refinement. Am I missing something? Best regards, Mark Mark Andrew White, Ph.D. Associate Professor of Biochemistry & Molecular Biology, Manager, SCSB Macromolecular X-ray Laboratory UTMB, Galveston, TX http://xray.utmb.edu

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Phenix.refine on coordinate-optimised structures
by Joey Farrell 08 Aug '20

08 Aug '20

Hello, I am trying to design a set of input parameters that I will be passing through the phenix.refine function. The structures that I am working with have already had their X,Y, and Z orthogonal Å coordinates optimised via separate protocol. I am looking for advice on which strategies and parameter values to use with phenix.refine to improve the crystallographic R-factors of such structures while preserving their earlier optimisation in real space. I have been having some success using “strategy = tls+individual_adp+occupancies” (where tls = “chain A”, tls = “chain B”, etc.) as well as adjusting the wxu_scale value until R-work and R-free are minimised. Are there other strategies or phenix.refine functionalities that may also prove helpful with this end in mind? I believe there may be ways to further improve R-work and R-free with this software that I am not yet aware of. Thank you for your help! Best, Joey

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Phenix Real_Space_Refine and Torsion NCS restraints
by Mark A. White 04 Aug '20

04 Aug '20

Hello, Are there plans to include Torsion Angle NCS restraints in the Phenix.Real_Space_Refine module? At low resolution (~ 3-4Å) I would like to include NCS restraints, but my molecule is flexible and the strict NCS constraints used in the Real_Space_Refine module are not appropriate. I am currently using phenix-1.18.2-3874. Best regards, Mark

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map to model - DNA model building
by Manoj saxena 04 Aug '20

04 Aug '20

Hello, I am trying to fit a cryo-EM map of a DNA protein complex (3.3 A) using the map to model in Phenix 1.18.2.3874, with a DNA sequence input in fasta format and the map as a .ccp4 file. However the output model fitted in the map I am getting is many fragmented PDB files and only one chain of DNA. What is the best way to get a higher fraction of the DNA model fitted into the map, can I switch off the segmentation of map and get both strands fitted into the map. Or the only option is to manually build? Thanks for your help Regards Manoj Saxena

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Model moving out of map
by Shanti Pal Gangwar 03 Aug '20

03 Aug '20

Dear all, I am trying to refine a Cryo-EM map at a decent resolution. The model was fit into the map in chimera and refined against the same map in Real space refinement in Phenix but after the run, a significant part of the model moved out of the density. I would appreciate any suggestion/strategy to solve this issue. Thank you Shanti Pal

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Postdoc position at UT Health Science Center, San Antonio, Texas
by Yogesh Gupta 03 Aug '20

03 Aug '20

The laboratory of Dr. Yogesh Gupta at University of Texas Health Science Center in San Antonio is seeking an enthusiastic Postdoctoral Fellow to study the structure and function of nucleoproteins in infectious diseases and cancer. We combine structural biology tools (X-ray, cryo-EM, NMR) with cell-based methods to address mechanistic questions and exploit this knowledge for drug development. Please visit below websites to learn about our research program – https://www.nature.com/articles/s41467-020-17496-8 *http://ccri.uthscsa.edu/YGupta.html <http://ccri.uthscsa.edu/YGupta.html>* Preference will be given to applicants with demonstrated experience in macromolecular crystallography. Candidates are expected to possess strong organizational, interpersonal skills, and ability to work as part of a team. An ideal candidate should hold (or soon expect to hold) a Ph.D. or equivalent degree in biochemistry/biophysics/structural biology and have no more than 2 years of postdoc experience. Salary is competitive. San Antonio offers affordable cost of living and there is no state income tax in Texas. If interested in applying, please send a short description of your research accomplishments, and CV with a list of 3 references to Dr. Yogesh Gupta (email: *guptay(a)uthscsa.edu <guptay(a)uthscsa.edu>*). The Greehey Children’s Cancer Research Institute is a unique specialized cancer research center focusing on basic and translational research in childhood cancer and occupies a state-of-the-art 100,000 sq. foot research facility on the university’s Greehey Academic and Research Campus. San Antonio is the nation’s seventh largest city and is located at the edge of the beautiful Texas Hill Country. San Antonio offers a rich, multi-cultural community, affordable cost of living, excellent weather and a thriving biomedical industry.* All Postdoctoral appointments are designated as security sensitive positions. The University of Texas Health Science Center at San Antonio is an Equal Opportunity/Affirmative Action Employer including protected veterans and persons with disabilities.* Thank you very much for your time. Yogesh -- Yogesh Gupta, PhD Assistant Professor of Biochemistry & Structural Biology PI, Greehey Children's Cancer Research Institute University of Texas Health Science Center 8403 Floyd Curl Drive, San Antonio, Texas, USA 78229 http://ccri.uthscsa.edu/YGupta.html

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Fwd: Sanofi Postdoctoral Fellowship: Computational Scientist for Antibody Engineering (Greater Boston, MA)
by yanfeng zhou 01 Aug '20

01 Aug '20

If you have strong interest in one of the following areas, please continue to read and check the link for more details. 1. Developing new algorithms to revolutionize biologics discovery 2. Challenging yourself with large and unique datasets and converting your learnings to tools/products that can help patients 3. Engineering of antibody, nanobody, and other biotherapeutics modalities 4. Learning how scientists from various training backgrounds collaborate together to discover and deliver faster and better biologics treatments. The Protein Engineering group within Sanofi Large Molecule Research Department is seeking a highly talented Computational Scientist for a postdoctoral position. We use leading-edge structural biology and computational tools to support biologics project needs from Sanofi’s multi-targeting, multi-modality research pipeline. Our team has a great track record of patents and publications, including Science, Nature Cancer, and Nature Communications, in the area of biologics characterization, antibody engineering and multi-specific antibodies. This postdoc project will focus on developing a machine learning approach to predict epitope-paratope, given any antibody-antigen pair, by combining in-depth understanding of structure biology, antibody engineering, and large datasets both internally and externally. The successful candidate will be with Ph. D. degree in related area and has an advanced understanding and practical experience with developing and applying complex machine learning solutions for structural biology data. The successful candidate will gain deeper insight into drug development process and transform AI/ML algorithms into accelerating biologics discovery and development process. Application Link: https://sanofi.wd3.myworkdayjobs.com/en-US/StudentPrograms/job/Framingham-M… *About Sanofi:* Every day, Sanofi's 100,000 employees are committed to improve the lives of people around the world, with sustainable and responsible solutions and initiatives. Sanofi is recognized as one of the leading biopharmaceutical companies in the world and is pioneering innovation in biologics with the first approved nanobody drug, the first clinical stage tri-specific antibody, and a novel genetic codon expansion platform for new engineering capabilities. Details of the organization and the company’s mission and goals can be found on our website (http://www.sanofi.us/l/us/en/index.jsp). ------------------------------ To unsubscribe from the CCP4BB list, click the following link: https://www.jiscmail.ac.uk/cgi-bin/WA-JISC.exe?SUBED1=CCP4BB&A=1 -- Yanfeng Zhou, Ph.D. Email: YanfengZhou.pku(a)gmail.com <yanfengzhou.pku(a)gmail.com>

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postdoctoral position at the Institute for Protein Innovation in Boston, USA
by Christopher Bahl 29 Jul '20

29 Jul '20

The Bahl Lab <http://function-structure.org/> at the Institute for Protein Innovation (IPI) in Boston is recruiting Postdoctoral Fellows. We use protein design to accelerate drug discovery and to engineer new lead therapeutic molecules. In addition to traditional academic collaborations, we work closely with pharmaceutical and biotech companies, as well as venture capital firms. We are looking for translationally-minded scientists who want their work to have a direct impact on the world. We will provide training in computational protein design using Rosetta, including de novo protein design and the design of protein function and biophysical properties. Postdoctoral Fellows at IPI leverage our high-throughput automated laboratory infrastructure. We are especially excited to expand our work in the following research areas: - prediction and design of protein developability for therapeutic applications - engineering of de novo miniprotein/peptide lead therapeutics for oncology, infectious disease, hypertension and diabetes, etc. - antibody design, including de novo paratope design - enzyme design Strong candidates will have demonstrated expertise in one or more of the following: - protein biochemistry: protein production and biophysical characterization, enzymology - structural biology: cryo-EM, X-ray crystallography, NMR - immuno-oncology: cell culture models, fluorescence activated cell sorting - traditional protein engineering: directed evolution, library construction, yeast and/or phage display - computational biology: machine learning, data science, molecular dynamics and/or modeling If you are excited to join a team of protein designers working to tackle audacious projects aimed directly at improving human health, please send your CV to: chris.bahl(a)proteininnovation.org About IPI The Institute for Protein Innovation is a non-profit organization that is advancing protein science to accelerate research and improve human health. The Institute is located at Harvard Medical School. IPI uniquely combines the freedom of academic exploration with the high-throughput scaling of industry to take on transformative protein-based initiatives that no other laboratory or organization can or will pursue. IPI is deploying state-of-the-art technologies to build a repository of powerful protein tools and reagents and share them through licensing and collaboration. These will enable new biomedical and therapeutic discovery for researchers in academia and industry alike. This constellation of vanguard technology and expertise positions IPI to train the next generation of entrepreneurs and protein scientists to lead the discovery of new medicines. The IPI is an equal opportunity employer and prohibits discrimination based on ethnicity, religion, sexual orientation, gender identity/expression, national origin/ancestry, age, disability, socioeconomic status, marital or veteran status, etc. Candidates from underrepresented backgrounds are especially encouraged to apply. -- PLEASE NOTE: This message, including any attachments, may include privileged, confidential and/or inside information belonging to IPI. Any distribution or use of this communication by anyone other than the intended recipient(s) is strictly prohibited and may be unlawful. If you are not the intended recipient, please notify the sender by replying to this message and then delete it from your system. Thank you.

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Re: [phenixbb] Phaser-MR output after each component placement
by Randy Read 28 Jul '20

28 Jul '20

Hi Boaz, At the moment, that is indeed the only thing you can do with the partial solution information from the log file. In the CCP4 environment, you can cut and paste lines from the log file to make a .sol file, and use that to run something like a refinement job to produce a PDB and MTZ for a partial solution, but the Phenix environment uses Python pickle files to store the transformations, so that option doesn’t apply. (Unless you run Phaser from a script, in which case the Phenix and CCP4 versions work the same.) At one point, Phaser was writing out a PDB file for the top solution at every point in the process, but we felt that led to clutter and that it was confusing. There’s a major rewrite going on at the moment, and the new phasertng will primarily be run through the phaser.voyager pipeline. One of the design criteria here was to be able to examine branches that weren’t taken or intermediate points in the ongoing search, and to be able to work with them while the overall job is still running. So there will be a better option in the hopefully not too distant future! Best wishes, Randy ----- 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 > On 27 Jul 2020, at 23:02, Boaz Shaanan <bshaanan(a)bgu.ac.il> wrote: > > Hi, > The closest option that comes to mind to do what you're looking for is to take the Euler angles+translations for each of the monomers in the .sol file (or at the top of the final pdb file) and apply each of them to the initial model using any transformation program of your choice. > I am more familiar with running Phaser using the ccp4 gui but it shouldn't be very different under Phenix. > Phaser people may well suggest a more elegant option. > Stay safe, > Boaz > > Boaz Shaanan, Ph.D. > Department of Life Sciences > Ben Gurion University of the Negev > Beer Sheva > Israel > > On Jul 27, 2020 16:02, Johannes Cramer <johannes.cramer(a)gmail.com> wrote: > Dear phenix board, > > does anyone of you know if there is an option in phaser-MR to output a pdb after each placed component? > For example: I suspect there to be 5 molecules in the AU. I start a replacement with 5 molecules and phaser places 1 (I would like to inspect that), 2 (again, I would like to look at the e.g. top 10 results), 3 and so on... > Is that possible? I couldn't find the option in the gui or in the phenix documentation, but maybe in the CLI? > I know I can run one after the other, but that would potentially waste CPU time until I find time to inspect them. > > Cheers, > Johannes > _______________________________________________ > phenixbb mailing list > phenixbb(a)phenix-online.org > http://phenix-online.org/mailman/listinfo/phenixbb > Unsubscribe: phenixbb-leave(a)phenix-online.org

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Visiting Research Specialist Position at the University of Illinois to Study Ribosome Structure
by Yury Polikanov 28 Jul '20

28 Jul '20

The Polikanov Laboratory at the University of Illinois at Chicago (IL, USA) is looking for a talented, skillful, and highly motivated researcher to fill the *Visiting Research Specialist* position to study the structure and function of the bacterial ribosome. The research in the Polikanov Laboratory is focused on understanding the basic principles of protein synthesis in bacteria, the modes of action of ribosome-targeting antibiotics, and the mechanisms of drug resistance at a structural level. More information about Dr. Polikanov's research can be obtained from the most recent publications ( https://www.ncbi.nlm.nih.gov/sites/myncbi/yury.polikanov.1/bibliography/503…) or found on the laboratory web-page ( https://bios.uic.edu/bios/people/faculty/yury-polikanov). The successful candidate will be involved in the determination of high-resolution structures of ribosome functional complexes with various protein translation factors, tRNAs, and antibiotics using macromolecular X-ray crystallography and potentially cryo-EM techniques. *Basic qualifications:* - BS degree in chemistry, biochemistry, biophysics, or a related field; - MS degree or higher is preferred; - Minimum 3 years of laboratory research experience; - Strong background in biochemistry and molecular biology; - Practical skills with the most standard methods currently used in molecular biology, and biochemistry (such as protein expression, purification); - Experience in structural biology (cryo-EM or X-ray crystallography) is desired; - Experience in RNA biology is desired. *The successful candidate is also expected to:* - Act independently in terms of planning and executing the experiments; - Compile, analyze, and prepare data for publications; - Assist with training of graduate and undergraduate students. For fullest consideration, please submit an application and cover letter describing your scientific interests and how your previous research accomplishments and scientific interests fit with the scope of the research in the Polikanov research group at https://jobs.uic.edu/job-board/job-details?jobID=133847 by August 14, 2020. The University of Illinois at Chicago is an Equal Opportunity, Affirmative Action employer. Minorities, women, veterans, and individuals with disabilities are encouraged to apply. The University of Illinois may conduct background checks on all job candidates upon acceptance of a contingent offer. Background checks will be performed in compliance with the Fair Credit Reporting Act.

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Phaser-MR output after each component placement
by Johannes Cramer 27 Jul '20

27 Jul '20

Dear phenix board, does anyone of you know if there is an option in phaser-MR to output a pdb after each placed component? For example: I suspect there to be 5 molecules in the AU. I start a replacement with 5 molecules and phaser places 1 (I would like to inspect that), 2 (again, I would like to look at the e.g. top 10 results), 3 and so on... Is that possible? I couldn't find the option in the gui or in the phenix documentation, but maybe in the CLI? I know I can run one after the other, but that would potentially waste CPU time until I find time to inspect them. Cheers, Johannes

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Adjusting pixel size using phenix
by Noor Agip 23 Jul '20

23 Jul '20

Hi, Is there a way to adjust pixel size of a volume in phenix? I have been using ResolveCryoEM and I would now like to calibrate the pixel of the resulting map. This could be done in chimera but requires resampling the map to a RELION map of the correct pixel size. Best wishes, Noor

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Heme geometry restraint
by Yangqi Gu 21 Jul '20

21 Jul '20

Dear all, I have a question regarding the heme c geometry restraint. I am aware that heme c could undergo distortion when bound to protein, but I am not sure at what resolution I could claim such distortion (such as ruffling/bending/doming). I have a map at 3.6 A resolution and whenever I did the refinement in phenix with real space refinement, some of the hemes are distorted and I am wondering if it is justified to leave it that way or do I have to impose the flat plane geometry. If so, how should I proceed to impose such geometry? Thank you in advance! Best, Yangqi

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mr_rosetta question
by Wei Wang 18 Jul '20

18 Jul '20

Dear all, I would like to get help on a mr_rosetta run. I have a case that 5 copies of searching model was found by Phaser, and I would like to find the sixth one. In addition I would like to improve the building of the MR solution. In such case I’m considering a mr_rosetta run, with some parameters like this: phenix.mr_rosetta seq_file=seq.dat search_models=placed_5_copies.pdb already_placed=true ncs_copies=1 … My question is, should I use the already placed 5 copies model as search_models, with ncs_copies=1, or should I use the original searching model with ncs_copies=6 (in this case I guess I should get rid of the other four copies from the result of Phaser)? For seq.dat, should I use the sequence from one copy of searching model, or paste 5 copies into the seq.dat? Thanks, Wei

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ligand possibly bound to active site cysteine
by Jorge Iulek 18 Jul '20

18 Jul '20

Dear all, I am refining a structure of a Glyceraldehyde 3-phosphate dehydrogenase (GAPDH) (converts glyceraldehyde 3-phosphate into D-glycerate 1,3-bisphosphate) , https://www.brenda-enzymes.org/enzyme.php?ecno=1.2.1.12 . <https://en.wikipedia.org/wiki/Glycerate_1,3-bisphosphate> It turns out that its active center cysteine presents bound ligands , covalently or not to be determined if possible (data resolution 2.51 A). I would like to get help on two issues, (1) what the ligand might be and (2) how to treat it (correct me) in phenix.refine. 1) The protein was expressed in E. coli; it had much contact with glycerol and crystallization conditions include the "ethylene-glycols-mix" ("a mixture of diethylene glycol, triethylene glycol, tetraethylene glycol, and pentaethylene glycol"). Nevertheless, no NAD cofactor was added, and there is no electron density for it. Otherwise, phosphate was also present in crystallization condition. In a previous study, I learned that glycerol might also contain minor amounts of ethylene glycol. I wonder, nevertheless, about glyceraldehyde (and note resemblance with the substrate). Catalytic mechanism includes a hemithioacetal intermediate (https://febs.onlinelibrary.wiley.com/doi/abs/10.1046/j.1432-1327.1998.25204… ) such that cysteine SD is bound covalently to a carbon. I wonder also how much this might attack an ethylene glycol and their likes. Pictures for the density are shown at for the 4 monomers of the a. u., first 4 photos: https://photos.app.goo.gl/Y7MyugqwRFD4sjgDA (blue 1 sig for e. d. maps, green 3 sig for Fourier difference maps) . Density is different among them to different degrees. The nearby threonine, in some cases, seems to interact with a blob (and it is helped by other threonine and a serine) which + - might accommodate a phosphate. I have tried to fit a number of molecules, e.g., the substrate (but not really good in all monomers for the phosphate moiety), glycerol, ethylene glycol and its di and tri (found also in other places in the structure) and now I went for glyceraldehyde (though, I have doubts that there is other - apart from the one eventually bound to S - tertiary carbon). Apart from the difficulties on searching for the best fitting molecule (and consider their intrinsic flexibility) I do not manage to establish distance between them and Cys SD (and there goes the second question). 2) I could not devise how to set a proper distance between any of the ligands and the Cysteine, be it to check for a covalent bond or to establish a van der Waals restriction. I tried: bond { action = *add delete change atom_selection_1 = chain A and resid 153 and name SG atom_selection_2 = chain N and resid 5 and name C3 symmetry_operation = None distance_ideal = 1.803 sigma = 0.1 slack = None limit = -1.0 top_out = False } Results are also show for my Glyceraldehyde trial, last 4 photos, https://photos.google.com/album/AF1QipO71L7GJYKv_MmjTc_0GzsH2xtFR_V-2ICBirPb . Note clashes. Curiously , for some of the bonds to be added, I receive the message: " Atom "HETATM 9835 O2 3GR N 5 .*. O " rejected from bonding due to valence issues." which seems to point to oxygen atoms, though I declare carbon atoms. Helps welcome, thank you. Jorge

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mr_rosetta build test
by Wei Wang 18 Jul '20

18 Jul '20

Dear all, I would like to ask a question about the testing of mr_rosetta build. Is the “phenix_regression.wizards.test_command_line_rosetta_quick" still available? I checked my early build on Mac it is there, but that build was ~3 years ago. However on a recent build on Ubuntu 18.04 the option is not available (I ran the rosetta.run_tests and it’s ok though). Regards, Wei

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occupancy_sum_constraints
by Petros Giastas 15 Jul '20

15 Jul '20

Dear all, I have a metal compound interacting with a protein and I am facing the following problem. Initially, the metal is equatorially complexed with chlorides, which are progressively exchanged by water molecules. This hydrolysis is clear from our spectroscopic analysis, but also from the anomalous maps, which show weaker peaks for the most exposed chlorides. The question regarding phenix.refine is: How can I refine the occupancies of the alternative species (chlorides and water molecules) and to constrain their sum into the occupancy of the metal, which is also under refinement? I cannot find the proper selection syntax to deal with this situation. Can you help me on that? Thank you in advance. Petros P.S. I remember I could treat this kind of problem with shelxl but it has been a lot of time since I last used shelxl for high resolution protein refinement and I would not like to go back.

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