- phenixbb - phenix-online.org

Postdoc position in methods development at LBNL
by Dorothee Liebschner 22 Nov '19

22 Nov '19

Announcing a postdoc position on behalf of Dr. Kanupriya Pande: ======================================================================== Post-doc position in methods development in the Molecular Biophysics and Integrated Bioimaging division at LBL. The overall objectives of the project are to develop theory and computation to extract conformational heterogeneity and disorder from diffraction and imaging data. The position is available immediately with an initial appointment for 2 years with the possibility of renewal based upon satisfactory job performance, continuing availability of funds and ongoing operational needs. Qualified candidates must have a PhD in Biophysics, Physics, Mathematics, Chemistry, or related fields. Job description and how to apply: https://lbl.referrals.selectminds.com/jobs/computational-biologist-postdoc-… ======================================================================== -- Project 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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Re: [phenixbb] weight optimization in refinement
by Alexei Gorelik 22 Nov '19

22 Nov '19

Thanks! What I meant is, phenix.refine seems to run a number of optimization threads (usually 10-14) independent of the number of cores specified (for example, 4 or 8). If i specify 8 cores, is there a way to force it to run 8 weight optimizations? On Nov 22, 2019 1:24 PM, Pavel Afonine <pafonine(a)lbl.gov> wrote: Hi Alexei, Is there a setting to control the number of parallel weight optimization threads in phenix.refine? nproc parameter controls number of CPUs to be used in weight optimization. Also, is there a way to force phenix.refine to perform global real-space refinement (rsrg)? No. There is some built-in logic, phenix.refine does it when these conditions are met and it can un-do the result if it is not an improvement. Is there particular need to do this in your context? Pavel

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problems running refinement of shaken model against half map
by L. Hielkema 22 Nov '19

22 Nov '19

Hi all, For the validation of my model to my map in phenix 1.17.1 I tried to refine my shaken model (0.5Å) against my half map in phenix real space refine. However, whatever I try I get a weird behaviour in the FSC(Model-map), see the image below. It seems not to be able to reach 0 in the correlation, but keeps getting stuck at 0.1. I tried various things to solve this, but unfortunately nothing helps: - Using the other half map - Cut of the heterogeneous part of my model and map and refine this - Used refined data without using a mask for the last iterations - Used different resolutions to refine against - Tried data from someone else in the lab (same microscope, same imaging conditions), to check if I am doing something wrong (this gave good results) When doing the same refinement in Refmac5 in ccpem 1.4 it does seem to work, however I would not like to switch programs, because this will mess up my final model. Best, Lisa

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weight optimization in refinement
by Alexei Gorelik 22 Nov '19

22 Nov '19

Hi, Is there a setting to control the number of parallel weight optimization threads in phenix.refine? Also, is there a way to force phenix.refine to perform global real-space refinement (rsrg)? Most of the time, when the "real-space" option is selected, it only carries out rotamer fitting (rsrl). I do know there's a separate real-space refinement program in Phenix. Thanks!

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Secondary structure restraints
by Luca Pellegrini 20 Nov '19

20 Nov '19

I have a protein-DNA complex and would like to apply SS restraints. What is the best way to apply the SS restraints to the protein only, using the GUI? I have tried the following: Select ‘Use secondary structure restraints’ in the ‘Refinement Settings’ tab ‘Select Atoms’ In the Selection Editor window, 'Find Secondary Structures' Removed manually all nucleic acid restraints in ‘Base Pairs’ and Stacking Pairs’ tabs Save and close. However, phenix refinement keeps switching SS restraints for nucleic acids to True. Kind regards, Luca Luca Pellegrini, PhD Department of Biochemistry University of Cambridge Cambridge CB2 1GA United Kingdom lp212(a)cam.ac.uk tel.: 0044 1223 760469 https://www.bioc.cam.ac.uk/pellegrini-group/pellegrini-group @PellegriniLab

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Molybdenum cofactor refinement
by Cristiano Mota 20 Nov '19

20 Nov '19

Hi all, I'm using phenix.refine to refine a structure of a Molybo-protein at 1.9Å. The MGD cofactors (molybdopterin guanine dinucleotide) are being refined with a weird distorted geometry causing some clashes. The Fo-Fc maps show that something is going wrong in the aromatic rings interatomic distances. I'm using the readyset to pick up MGD and metal restraints. Am I using the right protocol? Best regards, Cristiano Mota -- *Cristiano de Sousa Mota* Postdoctoral Researcher, Macromolecular Crystallography Group UCIBIO / FCT - Universidade Nova de Lisboa 2829-516 Caparica, Portugal (00351 212948300, ext 10962) http://xtal.dq.fct.unl.pt/

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Deadline Extended to December 9th
by Nick DeHaan 20 Nov '19

20 Nov '19

Hi PhenixBB, Thanks for sharing information about the AIMS Awards with your colleagues! Many have told us they really appreciated it. We’ve had requests for more time - so we extended the deadline to December 9th! For anyone with a protein target of interest, the AIMS Award program can help you discover new molecular tools, start new drug development efforts, and get published. The program is open to investigators, postdocs, and graduate students worldwide. We encourage you to check out our flyer for more information: Flyer <http://bit.ly/37oIrS3> You can apply directly on the website: atomwise.com/aims. Please don't hesitate to reach out with any questions! Best, Nick Nick DeHaan, MsE *Partnering Executive* *Atomwise* <http://www.atomwise.com/> | *Better Medicines Faster* ᐧ -- Confidentiality Notice: The information contained herein is for informational purposes only. This message is private and the information contained in this message, including any attachments, contains information that may be confidential, privileged and/or proprietary. It is intended to be read only by the individual or entity to whom it is addressed. If you are not the intended recipient, please notify the sender by replying to this message, delete the material immediately from your system and note that you must not review, disclose, copy, distribute or take any action in reliance on or in reference to this message, including any attachments. No confidentiality, privilege, or property rights are waived or lost by any errors in transmission. Any unauthorized use or disclosure of the contents of this message is not permitted and may be unlawful.

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cryo-EM density modification
by Tom Terwilliger 19 Nov '19

19 Nov '19

Hi Phenix cryo-EM users, For those of you trying out density modification for cryo-EM (phenix.resolve_cryo_em), the automatic estimation of resolution in the current version uses unmasked resolution instead of masked, in some cases resulting in running density modification at too low a resolution. Consequently it is best with this version if you specify your nominal resolution. To run it you can type: phenix.resolve_cryo_em half_map_1.ccp4 half_map_2.ccp4 \ seq_file=seq.dat resolution=3.5 or something like that. It requires the current nightly build to run. You might also want to wait just a short while and a version that has this and a few other bugs fixed, a GUI, full documentation, and an example dataset will be out (hopefully this week). The full description of the method is at https://www.biorxiv.org/content/10.1101/845032v1 Let me know of any problems or suggestions! All the best, Tom T -- Thomas C Terwilliger Laboratory Fellow, Los Alamos National Laboratory Senior Scientist, New Mexico Consortium 100 Entrada Dr, Los Alamos, NM 87544 Email: tterwilliger(a)newmexicoconsortium.org Tel: 505-431-0010

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Differences in refinement statistics
by Chancievan Thangaratnarajah 19 Nov '19

19 Nov '19

Hello, I have noticed differences in the refinement statistics between two different Phenix versions (see attachments) even though I am using the same cryo-EM map and model as input. The most notable difference are rotamer outliers, which were 0 % in Phenix 1.16-3549 and now 6 % in Phenix 1.17-3660. I was wondering whether anyone has noticed a similar behaviour? Or is there something that I have missed? Best, Chancie.

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Error in sequence assignment
by Tom Terwilliger 18 Nov '19

18 Nov '19

Hi Nicholas, I'm afraid there isn't a way to say which sequence goes with which chain. I would suggest using the tool phenix.replace_side_chains. Give it 1 chain and 1 sequence and if they have the same length it should just put it in. If it doesn't work, try phenix.sequence_from_map which can do the same thing. Let me know if that doesn't do it! All the best, Tom T Date: Sun, 17 Nov 2019 17:07:16 -0500 From: Nicholas Gao <dominion146(a)GMAIL.COM> Subject: Specify chain assignment in sequence file for rebuild-in-place of phenix.autobuild Dear CCP4, I currently have an MR solution that has the wrong sequence. The pdb file of the solution contains 3 chains, and I'd like to use the rebuild-in-place functionality within phenix.autobuild to correct the sequence of all 3 chains. Phenix allows me to supply a sequence file as input for this job, it's not clear to me how I tell the program which sequence should be assigned to which chain. Anyone know how to do this? Sincerely, Nicholas Gao -- Thomas C Terwilliger Laboratory Fellow, Los Alamos National Laboratory Senior Scientist, New Mexico Consortium 100 Entrada Dr, Los Alamos, NM 87544 Email: tterwilliger(a)newmexicoconsortium.org Tel: 505-431-0010

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