Showing posts with label pdb. Show all posts
Showing posts with label pdb. Show all posts

19 March 2013

363. Generating an image in PyMol

For some reason I needed to quickly generate a publication quality figure of a protein.

Deep View (SWiss PDB viewer) isn't available for linux anymore, and the old versions rely on 32 bit libs (which is increasingly a headache on debian). Rasmol is a classic, but I haven't used it properly since 1997 -- and all attempts at exporting png, jpg etc. failed on my debian wheezy box.

Jmol is awesome, and while I managed to make some pretty convincing figures I never quite got to where I wanted.

So I tried pymol

Pymol, like rasmol and jmol, has a visual interface which can be controlled via an integrated terminal. The learning curve is steep, but it's quick and easy to make figures once you've got the basics.



Install pymol from the repos in debian:
sudo apt-get install pymol

(on Archlinux you can get it via AUR  -- you'll need to install python-pmw first)

Download 1SU4.pdb from here http://www.rcsb.org/pdb/explore.do?structureId=1su4

In the directory where your pdb file is, do

pymol 1SU4.pdb
select helices, chain A
Click on the A(ction) by (helices), select preset/publication.

 select calcium, (res 995-996)
 show spheres, calcium

 Note that 'helices' and 'calcium' are just handles or aliases that I made up.

 alter calcium, vdw=5
 show spheres, calcium

 color purple calcium
 bg_color white

 set antialias=1
 set sphere_mode=5

where sphere_mode 5 means shading.

 ray 1000,1000

 save 1SU4.png

And here's the final figure: