- ChimeraX-users - RBVI Mailing Lists

question about pb file
by Renee Garza 02 Apr '24

02 Apr '24

Hi there! I've been saving pb files and see that the colors are of varying shades and transparency. I have looked at the link regarding the color key however some colors in the pb files are not in the list. I'm wondering if there's a place to look at the degree of confidence based on color somewhere or a way to have the output with the general color like red, blue, orange, yellow, etc. instead of very specific shades. Thanks, Renee

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Range selection dose not work.
by 洪冉 02 Apr '24

02 Apr '24

Dear Users and Developers of ChimeraX, I am attempting to make a selection of a range of atoms by their numbers in ChimeraX. However, the command I have used does not seem to work in my case. The command in question is sel #1:@1-3. Could anyone assist me with this issue? For screenshots, please see below. Many thanks in advance! Ran

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Can α-carbon trace and bond be adjust for PBC?
by qz.chen＠tamu.edu 01 Apr '24

01 Apr '24

Hi, I want to use ChimeraX to visualize the protein slab simulation in the condensed phase as the link below. Unlike typical protein simulations, simulations of the condensed phase slab often need to keep the atoms inside the box for more accurate visualization. This means that particles between proteins may be jumping, leading to unreasonable lines appearing in the visualization. I have not found a way to adjust this in ChimeraX. https://www.biorxiv.org/content/10.1101/2020.08.05.237008v1.full Is there a way to limit the maximum distance between carbon and bond among particles? Thanks!

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Define axis along z?
by Oliver Clarke 01 Apr '24

01 Apr '24

Hi, For symmetric EM volumes, it would be useful to be able to easily create an axis corresponding to the molecular symmetry axis - generally coincident with a vector parallel to the Z-axis of the box, directly through the center. Is there an easy way to create such an axis in ChimeraX for an arbitrary map? It would be useful to have such an axis in order to rotate a volume around the molecular symmetry axis, even in the absence of a model (this is fairly easy to do if a model is present using define axis). This might be a useful generic extension to "define axis", if there isn't already an easy way to do so. Cheers Oli

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Difficulty with Z-translation - bug?
by Oliver Clarke 01 Apr '24

01 Apr '24

Hi, I can't seem to get the mousemode "Z-translate selected models" to work properly. I have "translate selected" set to Alt+left-drag, so per the docs ("assigned button + Ctrl (in that order) switches to Z-translation instead"), Alt+Ctrl+left-drag should translate the selected model in Z. It does not, or at least in any reproducible manner. Watch the selected yellow marker in the side view here on the right hand side: https://www.dropbox.com/scl/fi/vds0cwu0zizclg64vlxqc/z_translate_bug.mov?rl… 1. Initially I translate in x-y using Alt-drag - works fine. 2. I try to translate in z using alt-ctrl-drag - nothing happens 3. I keep trying translate in z, and eventually it "works" - but if you look closely you will see that the movement of the marker is not synced up with the direction/speed of the mouse cursor. Is this a bug? I remember testing this when it was initially implemented and I thought it worked fine so I suspect so...? Cheers Oli

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*.mdb files from MOE (chemcomp)
by Krishnan Raman 29 Mar '24

29 Mar '24

how to convert docking poses from MOE software to be read into chimerax? thanks Krish CONFIDENTIALITY NOTICE This email, including any attachments, may contain confidential or legally privileged information that is intended only for the individual or entity to whom it is addressed. If you are not the intended recipient, please be advised that any dissemination, distribution or copying of this email and any attachment is strictly prohibited. If you have received this email in error, please reply to the sender so that BioCryst Pharmaceuticals, Inc. can take corrective measures and then permanently delete this email and any attachment, including any printed copies. Thank you.

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pTM and ipTM Score Access
by Haley V Goodwin 27 Mar '24

27 Mar '24

Hello! I am using ChimeraX to use AlphaFold Multimer. I have read from a couple of places that AF provides pTM and ipTM scores to evaluate the quality of the models. I was wondering how I access these values from ChimeraX. I have looked through the results zip file, but can’t seem to find where these values may be stored. Thank you so much for your help! Best, Haley Goodwin

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Re: isolde write phenixRsrInput (how to restrain ions?)
by Shahid, Taha (Dr.) 27 Mar '24

27 Mar '24

Hi Tristan, That worked perfectly - many thanks for your help! Phenix.metal_coordination didn’t like for_phenix.cif file created by Isolde write phenixRsrInput, but I was able to create the edits file by saving the model file as a PDB from ChimeraX directly. Cheers and happy Easter, Taha On 25 Mar 2024, at 16:15, Tristan Croll <tcroll(a)altoslabs.com> wrote: You don't often get email from tcroll(a)altoslabs.com. Learn why this is important<https://aka.ms/LearnAboutSenderIdentification> ***CAUTION:*** This email was sent from an EXTERNAL source. Think before clicking links or opening attachments. Hi Taha, I'm very glad you find ISOLDE useful! Regarding magnesium (and metal ions in general): ISOLDE itself doesn't currently try to write extra Phenix restraints for these, but you can use the program phenix.metal_coordination to generate an edits file that you can add to the phenix.real_space_refine input. That should automatically create a set of bond and angle restraints for all metals in the model. Best, Tristan On Mon, Mar 25, 2024 at 3:46 PM Shahid, Taha (Dr.) via ChimeraX-users <chimerax-users(a)cgl.ucsf.edu<mailto:chimerax-users@cgl.ucsf.edu>> wrote: Dear Tristan, I find ISOLDE invaluable for my work. Not only has it enabled me to build models of the highest quality, but been hugely instructive in giving me an instinctive ‘feel' for protein structure. I am having a minor problem with magnesium ions moving out of density when I run phenix.real_space_refine with settings output by isolde write phenixRsrInput. I typically specify restrainPositions true and includeHydrogens true as well. Is there a way to restrain these ions as well (perhaps an edit I could make to the real_space_refine.eff file)? Many thanks, Taha _______________________________________________ ChimeraX-users mailing list -- chimerax-users(a)cgl.ucsf.edu<mailto:chimerax-users@cgl.ucsf.edu> To unsubscribe send an email to chimerax-users-leave(a)cgl.ucsf.edu<mailto:chimerax-users-leave@cgl.ucsf.edu> Archives: https://mail.cgl.ucsf.edu/mailman/archives/list/chimerax-users@cgl.ucsf.edu/ Altos Labs UK Limited | England | Company reg 13484917 Registered address: 3rd Floor 1 Ashley Road, Altrincham, Cheshire, United Kingdom, WA14 2DT

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change chain description
by Joshua Arribere 27 Mar '24

27 Mar '24

Hello, When I load a pdb into chimerax, a table appears with the chain IDs and associated descriptions. I would like to change the chain descriptions. How do I do that? Thank you, J

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Apple's cpus for trajectory visualisation
by Enrico Martinez 26 Mar '24

26 Mar '24

Dear ChimeraX users ! I wonder about the performance on the modern Apple CPUs: using several Apple's models as a benchmark, I tested Chimera-X on the 2015 and 2017 iMacs equipped with the i7 8 cores and then on the 2023 Macbook Pro equipped with the Apple m2pro chip. In the end, although the modern hardware was much more stable (never mind when loading large netcdf trajectories, as I reported in the case of the 2015 iMAC), I only noticed a slight increase in performance during film editing. As a benchmark, I took a very large model containing the membrane with an embedded oligomer and loaded a trajectory of 5500 frames in Chimera-X. I used surface rendering with 0.4 grid spacing for everything. While everything worked fine, I was able to produce a short 30-second film of 750 frames in about 1h30 on the m2pro, which was almost the same as on my imac 2015. Is there any way to improve the performance of film-making on modern Apple CPUs? Many thanks in advance Enrico

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ChimeraX_question
by 杜博文 26 Mar '24

26 Mar '24

hello,  Chimerax will have an error when we want to use the ribbon inside color white command, please guide me to correct this mistake,Thx. 杜博文南方科技大学/研究生/研究生2021级广东省深圳市南山区学苑大道1088号  

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Re: Chimera X Matchmaker RMSD
by Elaine Meng 25 Mar '24

25 Mar '24

(CC-ing chimerax-users(a)cgl.ucsf.edu since that is the recommended address for ChimeraX questions as long as they do not include private data. Email sent to me directly has more chance of falling through the cracks.) Dear Dr. Sharyn Endow, The Matchmaker algorithm in ChimeraX is the same as in Chimera. So everything I said before about Chimera's Matchmaker is also the case in ChimeraX. If you have the "iteration" option turned on it doesn't use all aligned columns but instead prunes residue pairs for a better fit of the core. If you are showing the sequence alignment, it shows what set of positions were used for the final fit as a light orange colored box. As before, it uses only the CA-CA pairs within those columns, not the side chains. These overall RMSD values are reported in the Log. "pruned" refers only to the fit iteration process, where iteration prunes away some pairs so that they are not used in the final fit. See "Fitting" at the bottom of the "Matchmaker" help: <https://rbvi.ucsf.edu/chimerax/docs/user/tools/matchmaker.html#fitting> Or, if you are using the "matchmaker" or "mmaker" command, see the "cutoffDistance" option for the description of iteration and pruning: <https://rbvi.ucsf.edu/chimerax/docs/user/commands/matchmaker.html#options> If you mean the RMSD header across the top of the sequence alignment, that is a different thing calculated per column (not for the whole structures overall), and you can control in the Sequence Viewer Settings whether this RMSD histogram is calculated CA-only or backbone-only. Neither of them uses the sidechains. If a pairwise alignment, "CA RMSD" boils down to just the CA-CA distance. Simply selecting some range of residues on the sequence alignment doesn't change anything. See help for Sequence Viewer, its header lines, and its Settings: <https://rbvi.ucsf.edu/chimerax/docs/user/tools/sequenceviewer.html> <https://rbvi.ucsf.edu/chimerax/docs/user/tools/sequenceviewer.html#headers> <https://rbvi.ucsf.edu/chimerax/docs/user/tools/sequenceviewer.html#settings> Finally as mentioned in my previous answer about Chimera, you can use the "rmsd" command to calculate RMSDs over any sets of atoms that you choose (with or without sidechains) without changing the current positions of the structures. The more tricky part is that you have to specify in the command which atoms to pair with which atoms, since it is not calculated automatically like it is in Matchmaker. The syntax is a little different than in Chimera: there is a "to" between the two sets of atomspecs, and in ChimeraX the slash symbol "/" is used to indicate chains. "rmsd" command <https://rbvi.ucsf.edu/chimerax/docs/user/commands/rmsd.html> ChimeraX atomspec including many examples: <https://rbvi.ucsf.edu/chimerax/docs/user/commands/atomspec.html> I hope this helps, Elaine ----- Elaine C. Meng, Ph.D. UCSF Chimera(X) team Resource for Biocomputing, Visualization, and Informatics Department of Pharmaceutical Chemistry University of California, San Francisco > On Mar 23, 2024, at 8:09 AM, Sharyn Endow, Ph.D. <sharyn.endow(a)duke.edu> wrote: > > Dear Dr Elaine Meng, > > We wrote to you a few years ago regarding Chimera RMSD and you were kind enough to send the information below. We now have a few Q's regarding Chimera X Matchmaker, which displays RMSD values, e.g., when all beta-strands are selected in the Sequence Viewer window. > > • We would like to know what the RMSD values correspond to after aligning two protein sequences using Matchmaker Iwhich uses only only one point per residue for fitting) and selecting all b-strands in the Sequence Viewer window. Is a single RMSD value calculated for each residue to obtain the average RMSD for the "pruned" or all atom pairs and, if so, is the RMSD value between the single point per residue that was used for fitting? > > • Is there some way to obtain the C-alpha RMSD values but not the side chain values, after aligning two protein chains in Matchmaker in Chimera X? > > • What does "pruned" atom pairs mean in this context? > > T > hank you in advance for your help - > > Sincerely, > > Sharyn A. Endow, PhD > Professor of Cell Biology, DUMC > DUS, Cell Biology > PO Box 3709 / 245/247 Sands Bldg / 303 Research Drive > Durham, NC 27710 USA T 919 684-4311 F 919 681-9929 > > > > From: Elaine Meng <meng(a)cgl.ucsf.edu> > Date: January 25, 2021 at 4:26:34 PM EST > To: "Sharyn Endow, Ph.D." <sharyn.endow(a)duke.edu> > Cc: Chimera <chimera-users(a)cgl.ucsf.edu> > Subject: Chimera RMSD > Reply-To: Chimera <chimera-users(a)cgl.ucsf.edu> > > > From: "Sharyn Endow, Ph.D." <sharyn.endow(a)duke.edu> > Subject: Chimera RMSD > Date: January 23, 2021 at 11:27:17 AM PST > > Thank you for your work in developing Chimera. We are trying to use Chimera RMSD to quantitate twisting of a beta-sheet and would like to know what the syntax is to list rmsd values for specified residues corresponding to a beta-strand, not just for single residues. Is it possible to list these values using RMSD? If so, we would greatly appreciate knowing how to get started. > > Sincerely, > Sharyn > > Hi Sharyn, > You can specify any sets of atoms/residues that you like in the RMSD command, as long as there are equal numbers of atoms in the two sets that you specify (from two different models). They will be paired in the order specified. We have a command-line "atom specification" syntax for that kind of thing. There is a longish page with lots of examples here: > <https://www.rbvi.ucsf.edu/chimera/docs/UsersGuide/midas/frameatom_spec.html > > > In your case, you may need to specify residue numbers, chain ID, and possibly atom names if you just want to use alpha-carbons or backbone as opposed to all atoms of the residues. E.g. something like > > rmsd #0:12.A,57-63.A #1:14.A,59-65.A > > ... for all atoms of model 0 residues 12 and 57-63 in chain A vs. all atoms of model 1 residues 14 and 59-65 in chain A. Or to use CA-only or backbone only: > > rmsd #0:12.A,57-63.A@ca #1:14.A,59-65.A@ca > rmsd #0:12.A,57-63.A@n,ca,c,o #1:14.A,59-65.A@n,ca,c,o > > Of course the numbers could be the same in the two models, I just was trying to give a more general example. > I hope this helps, > Elaine > ----- > Elaine C. Meng, Ph.D. > UCSF Chimera(X) team > Department of Pharmaceutical Chemistry > University of California, San Francisco > > P.S. the chimera-users(a)cgl.ucsf.edu address CC'd here is recommended for general Chimera how-to or is-it-possible types of questions

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isolde write phenixRsrInput (how to restrain ions?)
by Shahid, Taha (Dr.) 25 Mar '24

25 Mar '24

Dear Tristan, I find ISOLDE invaluable for my work. Not only has it enabled me to build models of the highest quality, but been hugely instructive in giving me an instinctive ‘feel' for protein structure. I am having a minor problem with magnesium ions moving out of density when I run phenix.real_space_refine with settings output by isolde write phenixRsrInput. I typically specify restrainPositions true and includeHydrogens true as well. Is there a way to restrain these ions as well (perhaps an edit I could make to the real_space_refine.eff file)? Many thanks, Taha

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ISOLDE query - non crystallographic symmetry?
by Oliver Clarke 25 Mar '24

25 Mar '24

Hi Tristan, I've been using the latest version of ISOLDE with ChimeraX 1.7.1 and it is working beautifully - very smooth simulation and very helpful for fixing up problem areas! One query - is there any support for non crystallographic symmetry in ISOLDE, or if not is this on the roadmap? Thinking both in terms of NCS restraints, but also in terms of propagating edits from one subunit of an oligomer to all the others - this would be very helpful to have for a lot of folks I think, as so many proteins are oligomeric. Thanks for the wonderful piece of software! Cheers Oli

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Difficulty unsubscribing
by BARRY E DEZONIA 24 Mar '24

24 Mar '24

I am trying to leave this email list and currently am unable to. I send email to: chimerax-users-leave(a)cgl.ucsf.edu And it processes and says my email barry.dezonia(a)wisc.edu is not a list member. That is because I signed up with bdezonia(a)wisc.edu.. My mail service treats them as equivalent but it only sends out on the incorrect email address. Can someone unsubscribe ndezonia(a)wisc.edu? I can't figure out how to get my email client to use my other email address as the sending address.

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Adding lipid bilayers to chimerax movie
by Kevin Felt 24 Mar '24

24 Mar '24

Hello ChimeraX Users, I'm trying to make a movie in chimerax involving a membrane protein, and I would like to have some representation of where the inner and outer lipid bilayer leaflets are relative to the protein transmembrane region, ideally represented as phospholipids. Is it possible to do this within Chimerax? I've thought about encoding the movie to mp4 and then figuring out how to simply overlay a bilayer image onto the mp4 where I want with some other software , but I foresee resolution and scaling issues when doing that. Thank you! Sincerely, -- Kevin C. Felt PhD Candidate - Chakrapani Lab Department of Physiology and Biophysics School of Medicine Case Western Reserve University

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Color a surface by seq_conservation of neighboring residues
by Esser, Lothar (NIH/NCI) [E] 22 Mar '24

22 Mar '24

Hi, my intention is to make a figure that maps the degree of sequence conservation of surrounding residues onto a surface drawn over the said inhibitor. I know I can color surfaces by distances and other parameters but I could not find out how to color a surface by properties of neighboring residues or atoms. Is there perhaps a way to convert an atom attribute like conservation into a map that then could be used to color a surface? Alternatively, I thought I could write out the calculated sequence conservation as a pdb file with say the b-factor column representing the sequence conservation. Unfortunately, that does not seem to be the case. Can you write atom attributes in any other way? - perhaps I missed that. If I had access to the sequence conservation values, I could copy them to the b-factor column of the inhibitor and color its surface by bfactor. Thanks for any advice. Lothar NIH

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Visualisation of distances
by Enrico Martinez 21 Mar '24

21 Mar '24

Dear ChimeraX users ! I need to draw several distance vectors on the 3D structure. Could you provide me with an example of the commands that could automatically draw the distances between two selected atoms with some basic labels on it ? Many thanks in advance Enrico

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Re: Trying to join two structures unsuccessfully
by Maja Divjak 17 Mar '24

17 Mar '24

Alternatively, I guess I could just cut this disordered domain into fragments, move them around and the rejoin them.... -----Original Message----- From: Maja Divjak Sent: Tuesday, 5 March 2024 11:44 AM To: ChimeraX Users Help <chimerax-users(a)cgl.ucsf.edu> Subject: RE: [chimerax-users] Trying to join two structures unsuccessfully Dear Elaine, No worries at all, I have received multiple replies, so it is working! Thank you for your response below. Basically, it seems what I'd like to do can't really be done in this way. In another conversation, someone mentioned the tug command. Could this yield what I'm hoping for please? The two ends I'm trying to join are indeed in separate models, so I tried the following command: tug #16/a:345-355 toAtoms #18/A:345-355 which gave the following error: For 0 tugged atoms expected 0 destination atoms, got 84 Would this be the correct approach (I've clearly got the syntax wrong) or is there really no way to do this in Chimera X? Thanks so much and best wishes, Maja PS. How do I join the member's list please? -----Original Message----- From: Elaine Meng <meng(a)cgl.ucsf.edu> Sent: Tuesday, 5 March 2024 11:33 AM To: Maja Divjak <Maja.Divjak(a)petermac.org> Cc: ChimeraX Users Help <chimerax-users(a)cgl.ucsf.edu> Subject: Re: [chimerax-users] Trying to join two structures unsuccessfully ! EXTERNAL EMAIL: Think before you click. If suspicious send to CyberReport(a)petermac.org Dear Maja, Apologies if you are getting multiple copies of this answer from me. I keep getting error messages that my reply could not be sent to the list! So, here is my third try. If you've been getting my previous messages (even though I don't think the rest of the list is), please ignore and pardon me for the spam! Adding a bond only works when the atoms are in the same model as each other (typically a structure opened from one PDB file is one model). Also simply adding a bond won't move anything. It will just make a long bond between the atoms in their current positions, or if you choose "reasonable" only, it won't add any bond because the bond would be too long to be reasonable. <https://rbvi.ucsf.edu/chimerax/docs/user/tools/buildstructure.html#bonds> You can see what model(s) you have by looking in the Model Panel: <https://rbvi.ucsf.edu/chimerax/docs/user/tools/modelpanel.html> If the two atoms are in two different models (typically opened from two different input files), the "join models" Peptide Bond option should work if you really have exactly two atoms selected, the peptide terminal "N" in one model and the peptide terminal "C" in the other model. As far as I can tell these two are selected in your image, so I couldn't say why you get an error message. If the atoms are in the same model as each other, however, it will not work. You would need to split the model so that they are in separate models first. You can try command "info atoms sel" to list in the Log what you have selected. In my "join peptide" test case I get the following, which confirms I have the correct atoms from two different models selected: info atoms sel atom id #1/A:29@C idatm_type Cac atom id #2/A:1@N idatm_type N3+ However, join models is not going to change the conformation of the peptide, it will just move one model (e.g. the entire green one if it has more atoms than the purple one) as a rigid body to form the specified bond with the other model. <https://rbvi.ucsf.edu/chimerax/docs/user/tools/buildstructure.html#join> I hope this helps, Elaine ----- Elaine C. Meng, Ph.D. UCSF Chimera(X) team Resource for Biocomputing, Visualization, and Informatics Department of Pharmaceutical Chemistry University of California, San Francisco

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How to change transparency of ladder mode of nucleic acids
by Yan ZHANG 张艳 15 Mar '24

15 Mar '24

Dear ChimeraX Team, I hope this email finds you well. My name is Zhang Yan, and I am a beginner of ChimeraX. I am writing to seek assistance regarding how to change transparency of ladder mode of nucleic acids in ChimeraX. Despite trying the command 'trans #1 60 all', I have been unable to achieve the desired effect. Could you please suggest an alternative solution or provide guidance on how to accomplish this task? Thank you for your attention to this matter. Best regards, Zhang Yan

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Is the site down ?
by Marie PREVOST 14 Mar '24

14 Mar '24

Hello, I would like to install ChimeraX on my new laptop but the site seems to be down… Do you know if there are other option to download the installer ? Thank you for your help Best wishes ------- Marie Prevost, PhD Pierre-Jean Corringer’s lab ( site<https://research.pasteur.fr/en/member/marie-prevost/> ) Channel-Receptors Unit Institut Pasteur 25 rue du Dr Roux 75015 PARIS France +33 (0)1 53 55 15 06 (via Teams)

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Question about interpreting variable ipTM scores
by David S. Fay 14 Mar '24

14 Mar '24

Hi, This question isn’t specifically about chimerax, but I hope it’s in the ball park. For most of the protein pairs I’ve tested using multimer, the ipTM scores for the 5-10 models are relatively consistent. For example all 0.2–0.3, or 0.75–0.85, or 0.4–0.6. But occasionally I’ll get one or two very high scores (>0.7) with the rest being low or somewhat randomly scattered. My instinct, of course, is to put more faith in scores when the models converge. At the same time, I don’t want ignore a potentially real interaction. So, I’m wondering how people interpret ipTMs when the numbers are variable between models. What is the reason that some protein pairs show this pattern? Is the good score(s) indicative or something real or a false positive. Are the bad scores indicative of true or false negative? Any thoughts, insights, and possible follow up approaches would be greatly appreciated! David

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Downloading chimera
by Pincus, Seth 14 Mar '24

14 Mar '24

When I try to download Chimera (or connect to any Chimera site), I get the attached error message saying that “www.cgl.ucsf.edu has refused the connection”. I am running Chrome version 122 on a Mac Powerbook running OS12.7.1. My computer is owned by Montana State University and may have some additional security is installed. But I could find nothing in Chrome’s settings that would allow me to connect. Please respond bydirect e-mail, since I cannot get to the site to join the mailing list. Thank you, Seth Pincus, M.D. Professor Department of Chemistry and Biochemistry WWAMI Medical Program Montana State University Bozeman, MT 59717

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only make selection highlighted
by 张楠 13 Mar '24

13 Mar '24

Dear developers, How does chimerax make the stick I selected highlighted and the carton in other areas blurred? I tried to click on view selected, but that only makes the back of the structure blur, not the front. May I ask how to operate to achieve the effect in the picture, only highlight stick？ Looking forward to your answer, thank you！ Best regards, Nan 张楠 zhangnan(a)nankai.edu.cn

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Isolde can't be installed inside ChimeraX 1.5
by Jun Zhang 13 Mar '24

13 Mar '24

Hi ChimeraX, I met an issue when I try to install Isolde inside ChimeraX 1.5. It will stuck there forever. May I ask you if there are any ways to solve this issue? I tried to use website to download the whl file, but it can’t be recongized by ChimeraX. May I ask you for some suggestions if possible? Many thanks in advance and have a nice day! Best regards, Jun Zhang

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