Biochemistry Problem Set: X-Ray Question
 

  Choose the Best-Fit R-Group:

Residue 2:             
Residue 3:             
Residue 4:             

Five Amino Acid Residues in an Electron Density Map.
The Jmol image shows a short polypeptide, of sequence Gly-X-X-X-Gly, within its electron density map. The segment of a protein structure is initially shown as an Ala pentapeptide displayed as Backbone with beta carbons (if appropriate) and colored CPK. The meshwork surrounding the chain simulates the electron density contour from an X-Ray diffraction experiment.

Use the buttons (Labeled A-D) at the right of the model to find the best-fit amino acid residue at each of the three positions (residues 2, 3, and 4). The buttons leave each amino acid selected so that any combination of Display or Color can be used until another amino acid is selected.
(Please note: All 12 of the amino acid possibilities are falsely labeled, "ALA"; you need to identify the amino acid based on its sidechain.
Submit your proposed best-fit sequence along with an explaination of your approach. Feel free to submit an image of the fitted electron density with your problem set.