Hello, I think this thread from a few months ago will help.

https://www.jiscmail.ac.uk/cgi-bin/wa-jisc.exe?A2=ind2007&L=CCP4BB&D=0&P=49210

Best wishes, Jon Cooper

-------- Original Message --------
On 25 Nov 2020, 03:24, Cheng Zhang wrote:

> Hi everyone,
>
> This question must have been asked before but I couldn't find a good answer 
> online.
>
> I work on a cryo-EM structure with one serine residue covalently linked with 
> a lipid molecule. The map for the lipid moiety was there but not good enough 
> to unambiguously place each atom. I tried to manually model the lipid moiety 
> to fit the map. But if I refine it in real space, it would move away from the 
> serine residue even though I linked it to the residue in the PDB file. My 
> question is, how to refine such a modified residue in real space without 
> breaking the covalent bond? Is there any way to make a molecular topology 
> file for the lipid moiety that also contains restraints for the covalent bond 
> with the modified residue? Also, let's say there is an unnatural amino acid 
> in the protein, how to define this residue so COOT or Phenix can recognize it 
> as an amino acid and the peptide bond restraints still apply to it?
>
> Thanks!
>
> Cheng
>
> --
>
> ---------------------
> Cheng Zhang
>
> ---------------------------------------------------------------
>
> To unsubscribe from the CCP4BB list, click the following link:
> https://www.jiscmail.ac.uk/cgi-bin/WA-JISC.exe?SUBED1=CCP4BB&A=1

########################################################################

To unsubscribe from the CCP4BB list, click the following link:
https://www.jiscmail.ac.uk/cgi-bin/WA-JISC.exe?SUBED1=CCP4BB&A=1

This message was issued to members of www.jiscmail.ac.uk/CCP4BB, a mailing list 
hosted by www.jiscmail.ac.uk, terms & conditions are available at 
https://www.jiscmail.ac.uk/policyandsecurity/

Reply via email to