Re: [ccp4bb] artificial tetramer

2011-12-14 Thread Tim Gruene
-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 Hi Fred, this sentence of yours, All pdb's are superposed by a common sequence region, which also will be part of the tetramer interface. probably hides the information which would be necessary for a reasonable answer to your question. If you still

Re: [ccp4bb] artificial tetramer

2011-12-14 Thread Fred
Hi Tim, Thanks for your replay. All pdb monomers have the same primary sequence and a perfect matching long helix, which I have used to superpose the coordinates. Such helix is almost straight so that, the idea would be to create a vector along the helix main axis, shift this axis to a some

Re: [ccp4bb] artificial tetramer

2011-12-14 Thread Eleanor Dodson
This sounds as though you will create a 4-helical rod? There are lots of 4-helical bundles but they arenot completely rod like - there is a twist in most I have seen. Maybe you should do secondary structure matching to a suitable 4-helicl bundle, match your helix in turn to each of the bundle

Re: [ccp4bb] artificial tetramer

2011-12-14 Thread Herman . Schreuder
Dear Fred, In this case, I would take one monomer and edit the CRYST1 card of the pdb to have a sufficiently large tetragonal unit cell. Next I would manually align the helix of one monomer with the fourfold axis, e.g. the Z-axis. If you display the unit cell, you will get e.g. the 0,Z,0 axis to

Re: [ccp4bb] artificial tetramer

2011-12-14 Thread Tim Gruene
-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 Hello Fred, as far as I understand your problem I am not aware of existing programs to carry out the tasks. To automatise the process I would write a program myself which takes the PDB-file and the reside numbers which make that helix as input and:

Re: [ccp4bb] artificial tetramer

2011-12-14 Thread Eleanor Dodson
An old old trick for getting a straight helix along a crystal axis using the GUI. Run the Amore TABLING step - it is part of the GUI with the helix as your model. (See molecular replacement - amore suite.) Amore calculates the ppl axes and will align it along the Z axis .. Thank you Jorge..

Re: [ccp4bb] artificial tetramer

2011-12-14 Thread Phil Evans
I've done this sort of thing (but different) using the Clipper libraries in C++. I found it easier to write short programs to do specific tasks rather than try to write generic all-purpose tools Phil On 14 Dec 2011, at 15:07, Tim Gruene wrote: -BEGIN PGP SIGNED MESSAGE- Hash: SHA1

Re: [ccp4bb] very strange lattice: high anisotropy, 78% solvent content and maybe merohedral twinning

2011-12-14 Thread Stefan Gajewski
Jürgen, Have you checked a simple selfrotation function in your currently favored space group ? Yes, both selfrotation function and patterson map do not look suspicious in I422. Do you have sufficient data collected to start out in P1 or C2 ? Then I would start there and systematically

Re: [ccp4bb] very strange lattice: high anisotropy, 78% solvent content and maybe merohedral twinning

2011-12-14 Thread Bosch, Juergen
Give XDS a try with your data or d*trek with 3d profile fitting. Did you try iMosflm or the old Mosflm ? If old, then POSTREF WIDTH 15 might help and POSTREF FIX BEAM You saw the nice packing from Tjaard, if all your molecules have contact with each other than that's fine I was just concerned

Re: [ccp4bb] very strange lattice: high anisotropy, 78% solvent content and maybe merohedral twinning

2011-12-14 Thread Debasish Chattopadhyay
How about plotting the solvent content along with resolution limits of the structures? From: CCP4 bulletin board [mailto:CCP4BB@JISCMAIL.AC.UK] On Behalf Of Pavel Afonine Sent: Wednesday, December 14, 2011 12:02 AM To: CCP4BB@JISCMAIL.AC.UK Subject: Re: [ccp4bb] very strange lattice: high

Re: [ccp4bb] very strange lattice: high anisotropy, 78% solvent content and maybe merohedral twinning

2011-12-14 Thread Pavel Afonine
Hi Debasish, On Wed, Dec 14, 2011 at 9:23 AM, Debasish Chattopadhyay debas...@uab.eduwrote: How about plotting the solvent content along with resolution limits of the structures? here it is: Resolution Number of Solvent % (mean/min/max) Solvent % (mean/min/max) range structures

Re: [ccp4bb] PHENIX vs REFMAC refinement had me fooled

2011-12-14 Thread Ian Tickle
On 13 December 2011 17:59, James Holton jmhol...@lbl.gov wrote: A small but potentially important correction: FC_ALL PHIC_ALL from REFMAC are indeed the calculated structure factor of the coordinates+bulk_solvent, but AFTER multiplying by the likelihood coefficient D (as in 2*m*Fo-D*Fc ).  

[ccp4bb] off-topic: Phoenix robot problems

2011-12-14 Thread Gregor Witte
Dear CCP4ers, We are currently fighting with our crystallization robot and would be happy to find out if anyone else has experienced similar problems - and hopefully found a solution. To make a long and extremely frustrating story with our robot short: We are running an ArtRobbins 4-Channel

[ccp4bb] Hydrophobic interactions

2011-12-14 Thread Luthra,Amit
Hi Everyone I have to calculate hydrophobic interactions in pdb files. Is any server available for this type of calculation? Thanks in advance Amit

[ccp4bb] Mg or water?

2011-12-14 Thread bie gao
Hi every, I'm working with 2 crystal forms of a protein from 2 different crystallization conditions. Condition 1 has 100mM MgCl2. Condition 2 doesn't. Both are ~2.9 angstrom. The 2 structures are virtually identical except in condition1, there is a clear positive density surrounded by a Glu side

[ccp4bb] Pore Dimension Convention

2011-12-14 Thread Jacob Keller
Dear Crystallographers, is there a convention for denoting/measuring pore sizes in protein structures? Maybe inter-atom distances minus van der Waals radii? JPK -- *** Jacob Pearson Keller Northwestern University Medical Scientist Training Program email:

Re: [ccp4bb] Pore Dimension Convention

2011-12-14 Thread Michael Thompson
Hi Jacob, There are a number of programs that can calculate the radius of a pore. The one that comes to mind is called HOLE, and it can make a nice plot of the y-coordinate along the pore vs. pore radius. I don't recall exactly how this calculation is done, I think it is somehow related to the

Re: [ccp4bb] Hydrophobic interactions

2011-12-14 Thread eugene . krissinel
google on pisa pdbe -- Eugene From: CCP4 bulletin board [CCP4BB@JISCMAIL.AC.UK] on behalf of Luthra,Amit [alut...@uchc.edu] Sent: Wednesday, December 14, 2011 8:34 PM To: ccp4bb Subject: [ccp4bb] Hydrophobic interactions Hi Everyone I have to calculate