Hi guys,

ok so I really appreciate all the help.

I now have cif2mtz (setting up my bash file)  and also have looked at PDB_REDO 
(which I had never heard of).
Yes, for 1c75 (the example I used) when I searched on the EDS server it did NOT 
give a map but it did when I  used COOT (again I never tried this since looking 
directly on the server did not give a map, assuming it did not exist).

@Pete:
I was wondering what you meant by "another MTZ file"
So are you saying, I first download the 1c75-sf.cif then do cif2mtz

then I use FFT to get the second MTZ file?
(but this second MTZ file generation can be skipped if I open the 1st stage MTZ 
using COOT??)

Have I understood your reply correctly?

Thank you all once again for your help.
Patrick




> -----Original Message-----
> From: [email protected]
> Sent: Tue, 27 May 2014 16:50:41 -0500
> To: [email protected]
> Subject: Re: Structure factors to CCP4 maps
> 
> Hi Patrick,
> 
> For the majority of deposited structures, you need an additional step
> between 3 and 4.  Format conversion can be done using CCP4 program
> cif2mtz.
> 
> However, most deposited structures (including 1C75) don't include phase
> information, which is required for electron density calculation.  Phases
> can be calculated from the model using a variety of programs (this is
> "step 3.5").  This will give you another mtz file containing the
> amplitudes and phases, which can be used to calculate electron density.
> 
> MTZ files store reciprocal space data, some of which can be used to
> calculate real space data (aka a map) - but a MTZ file doesn't store a
> map (although this seems to be a common misunderstanding).
> 
> You'd use fft (also part of ccp4) to calculate a real-space map from a
> phased mtz file - but if you're goal is to visualize it in coot,
> auto-open mtz within coot usually works just as well.
> 
> Hope this helps,
> 
> Pete
> 
> RiC wrote:
>> I am NOT trying to open the CCP4 file on a text editor !
>> 
>> I am trying to do the following on CCP4/COOT:
>>  1) Download a PDB  (example 1c75.pdb) from the PDB database
>> 
>> 2) Download the corresponding structure factors (example
>> 1c75-sf.cif.txt)
>> 
>> 3) Now from the above sf-cif file How can I get a MTZ file using  CCP4
>> 
>> 4) Then display the map (either in CCP4 format or MTZ format) in COOT
>> 
>> I want to know how to do step 3 above.
>> 
>> Sorry, I was not more clearer earlier.
>> Patrick
>> 
>> 
>>     -----Original Message-----
>>     *From:* [email protected]
>>     *Sent:* Tue, 27 May 2014 17:31:47 -0400
>>     *To:* [email protected], [email protected]
>>     *Subject:* RE: Structure factors to CCP4 maps
>> 
>>     I am terribly sorry, but ccp4 maps are understandable to nobody.
>> They are
>>     binary files, for starters.  Even if you develop an uncanny ability
>> to read
>>     these you will still be left with random looking sea of numbers.
>> 
>>     If you trying to generate a model map, you can use sfall.  Given
>> that you
>>     are posting on coot bb, the easiest way to visualize such map is to
>> use Fc
>>     column from, say, zero step refmac run.
>> 
>>     Be more specific.  Look at pdb_redo, it may be what you are looking
>> for.
>> 
>> 
>>     Sent on a Sprint Samsung Galaxy S® III
>> 
>> 
>>     -------- Original message --------
>>     From: RiC
>>     Date:05/27/2014 4:42 PM (GMT-05:00)
>>     To: [email protected]
>>     Subject: Structure factors to CCP4 maps
>> 
>>     HI,
>> 
>>     Does anyone have a step by step guide to go from a structure factor
>> file
>>     from the PDB to a CCP4 map (understandable to a biologist)  like the
>> one I
>>     can download on the electron density server?
>> 
>>     I am confused and my attempts at using CCP4 keeps coming up with
>> "failed"
>> 
>>     Thanks
>>     Patrick
>> 
>>     ____________________________________________________________
>>     FREE ONLINE PHOTOSHARING - Share your photos online with your
>> friends and
>>     family!
>>     Visit http://www.inbox.com/photosharing to find out more!
>> 
>> --------------------------------------------------------------------------------
>> 3D Earth Screensaver Preview <http://www.inbox.com/earth>
>> *Free 3D Earth Screensaver*
>> Watch the Earth right on your desktop! Check it out at
>> www.inbox.com/earth
>> <http://www.inbox.com/earth>

____________________________________________________________
FREE 3D EARTH SCREENSAVER - Watch the Earth right on your desktop!
Check it out at http://www.inbox.com/earth

Reply via email to