Jmol/Visualizing membrane position
Here are two ways of visualizing the position of a lipid bilayer membrane around the integral membrane portion of a trans-membrane protein.
a hydrophobic vs. polar color scheme, the protein within the lipid bilayer is seen to have a largely hydrophobic surface. The example used here is 5lil. Methods: PseudoatomsAny protein structure that includes an integral membrane domain can have pseudoatoms added to the PDB file by the Orientations of Proteins in Membranes Server[1]. Structures in the Protein Data Bank are pre-processed; other structures may be uploaded to the server. The server removes hydrogen atoms from the model. You can download the pseudoatom-enhanced PDB file from the server, and then upload it to Proteopedia for use in a Molecular Scene. In the case of 5LiL, I had difficulty getting the pseudoatoms to show from a green link (even though they displayed in the SAT). In the PDB file, the pseudoatoms followed a MASTER record. I deleted the MASTER record and all CONECT records, and then I got the results shown above with File:5lil opm2.pdb. Methods: Translucent CylinderChoose boundary residuesFirst you must choose residues or atoms in the model that are closest to the ends of the desired cylinder. If you wish, you can use a pseudoatom-enhanced model to assist. Viewing the model in FirstGlance in Jmol, you can use Hydrophobic/Polar (Views tab) to visualize the domain with a hydrophobic surface. Touching or clicking on atoms at the domain boundaries will identify those amino acids. If you wish, you can center a particular residue, then zoom in, and see atomic detail with Vines/Sticks (Views tab).
|
|
ReferencesReferences
- ↑ 1.0 1.1 Lomize MA, Pogozheva ID, Joo H, Mosberg HI, Lomize AL. OPM database and PPM web server: resources for positioning of proteins in membranes. Nucleic Acids Res. 2012 Jan;40(Database issue):D370-6. doi: 10.1093/nar/gkr703., Epub 2011 Sep 2. PMID:21890895 doi:http://dx.doi.org/10.1093/nar/gkr703