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Constrained group refinement
by Christian Roth 08 Nov '11

08 Nov '11

Dear all, I defined the following contrained groups which should a ligand in two alternative forms and an ion at the same position refine to an summed occupancy of 1. constrained_group { selection = chain Z and resname 2CL and altloc A selection = chain Z and resname 2CL and altloc B selection = chain r and resname Cl } constrained_group { selection = chain c and resname 2CL and altloc A selection = chain c and resname 2CL and altloc B selection = chain m and resname Cl } constrained_group { selection = chain N and resseq 69 and altloc A selection = chain N and resseq 69 and altloc B selection = chain o and resname 2Cl } } At the end I get an error because of the very small nonbonded interactions. it seems that my definition are not correct, but I am at the moment unsure why. Could someone point me to the mistake. Thanks in advace for your help Best Regards Christian

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Constrained group refinement Addendum
by Christian Roth 08 Nov '11

08 Nov '11

Do the ions have to be altlocC for the group definition? Best Regards Christian

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Cross Validation Reflection Set question
by Yuri 07 Nov '11

07 Nov '11

Thanks for the replies. >I just tried doing this, and it looks like the R-free flags will cover >the full resolution range, at least with the current code. By current code, you mean 1.7.2-869 and newer, right? >Is this really necessary in this case (refine against lower res data, >then continue with the whole data set I think I have a backbone shift in this structure (relative to native protein used for MR) so I wanted to do it this way befor trying to go all the way down to 2A. One last question does phnix do NCS averaging to improve maps? -- Yuri Pompeu

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Re: [phenixbb] AutoBuild runtime
by Nathaniel Echols 07 Nov '11

07 Nov '11

On Mon, Nov 7, 2011 at 9:14 AM, Shya Biswas <shyabiswas(a)gmail.com> wrote: > Thanks for the suggestions. Unfortunately my MR solution is not good enough > to get a good map. Autobuild does give me a solution when i put in my > sequence but the map does not look good. I was wondering if the final model > that Autobuild gives has undergone density modification. Strictly speaking, it's the map that undergoes density modification - but yes, this will be done unless you explicitly disable it. -Nat

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Cross Validation Reflection Set question
by Yuri 07 Nov '11

07 Nov '11

Dear All, Here is the situation, I have data to 2 A. I refined the model to 3 A first with S.A. Now I want to use higher res data for the rest of refinement. My Rfree created in the first round when I only used data to 3A. Was Rfree set created using all the data or just up to 3A shell? or do I have to extend into higher res shells? one caviot is I had twin law h,-k,-h-l enabled when they were created. Thanks, -- Yuri Pompeu

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Re: [phenixbb] AutoBuild runtime
by Nathaniel Echols 05 Nov '11

05 Nov '11

On Sat, Nov 5, 2011 at 12:02 PM, Shya Biswas <shyabiswas(a)gmail.com> wrote: > I was running autobuild using my protein sequence and the best MR model that > I got out of phaser, however it is taking really long to finish the job. Is > there a way to reduce the time period? Several options: - turn on quick mode (quick=True, or equivalent button in GUI) - use multiple processors if you have them (nproc=X, or equivalent control in GUI) - cut back resolution: if you have really good and/or high-resolution data*, you may be able to get nearly as good a model with fewer reflections, and it will be much faster (mostly due to refinement time, I think). However, this can also significantly degrade your model if the data aren't that great. - instead of AutoBuild, use phenix.phase_and_build (also in the GUI), which is basically the building procedure from AutoSol. It will usually not produce as complete a model (or R-factors as low) as AutoBuild, but it's much faster. -Nat (* the p9-sad tutorial is a good example of this - when we run workshops, we usually tell attendees to set the resolution limit for AutoSol to 3.0 instead of using all data to 1.7. The resulting model is nearly complete, and it finishes in less than half the time. Of course these data are unusually good...)

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Call for submissions to Computational Crystallography Newsletter (corrected)
by Nigel Moriarty 05 Nov '11

05 Nov '11

Calling for articles and short communications of interest tostructural biologists. The deadline for publication in the January2012 issue is 1st Dec, 2011. The Computational Crystallography Newsletter (CCN) is an electronicnewsletter for structural biologists, and is published online every 6months. Feature articles, meeting announcements and reports can besubmitted to me at any time for consideration. Submission of text byemail or word-processing files using the CCN templates is requested.Past newsletters and the template are available atwww.phenix-online.org/newsletter. Cheers Nigel -- Nigel W. Moriarty Building 64R0246B, Physical Biosciences Division 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

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Call for subscriptions to Computational Crystallography Newsletter
by Nigel Moriarty 04 Nov '11

04 Nov '11

Calling for articles and short communications of interest to structural biologists. The deadline for publication in the January 2012 issue is 1st Dec, 2011. 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 the template are available at www.phenix-online.org/newsletter. Cheers Nigel -- Nigel W. Moriarty Building 64R0246B, Physical Biosciences Division 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

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metal coordination restraints
by Laurie Betts 04 Nov '11

04 Nov '11

How does PHENIX know where to look for proper bond lengths and angles for a metal ion I add to a protein structure - do I just add the metal into difference density and any waters, and then run ready set and it knows where to look for that particular metal and the atoms to which is is coordinated? And shouldn't there be a 'cif file that it outputs, or is that something that I need to get myself? Sorry it's still not obvious to me from the documentation. Thanks Laurie Betts

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Postdoctoral Position at King's College London, UK
by Steiner, Roberto 04 Nov '11

04 Nov '11

A three-year postdoctoral position in the field of mechanistic enzymology is immediately available in the Steiner Laboratory of King’s College London. The salary is £33,193 per annum inclusive of London allowance. The project aims at studying the intriguing biological process of cofactor-independent oxygenation catalysis (1). To understand how dioxygen chemistry takes place in a cofactor-less manner we will use enzymes for which we have recently obtained structural information in various catalytically relevant states (2). The ideal candidate has a strong biochemistry/chemistry background, extensive experience in structural biology focused on enzyme mechanisms and an interest in molecular dynamics (MD). The MD work will be carried out in collaboration with Prof. Ceccarelli of the University of Cagliari, Italy, where the postdoc will be able to spend some time to improve his/her skills in MD techniques. The postdoc will also be in close contact with the Manchester group of Prof. Scrutton where complementary spectroscopic and kinetic studies will be carried out. This project will equip the post-holder with a rare and sought-after skill-set as well as a comprehensive overview of an inter-disciplinary study. To apply for this position go to http://www.kcl.ac.uk/depsta/pertra/vacancy/external/pers_detail.php?jobinde…. Please make sure you quote the reference number G6/JKA/772/11-JT. Informal enquiries are welcome at roberto.steiner(a)kcl.ac.uk<mailto:[email protected]>. The closing date for this application is 24 Nov. 2011. (1) Fetzner S. and Steiner RA (2010). Cofactor-independent oxidases and oxygenases. Appl. Microbiol. Biotechnol. 86, 791-804. (2) Steiner RA, Janssen HJ, Roversi P, Oakley OJ, Fetzner S (2010). Structural basis for cofactor independent dioxygenation of N-heteroaromatic compounds at the •/•-hydrolase fold. Proc. Natl. Acad. Sci. USA, 107, 657-662. Roberto Steiner, PhD Randall Division of Cell and Molecular Biophysics Group Leader King's College London Room 3.10A New Hunt's House Guy's Campus SE1 1UL, London, UK Tel 0044-20-78488216 Fax 0044-20-78486435 roberto.steiner(a)kcl.ac.uk<mailto:[email protected]>

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