PDBsum entry 1ejg

Go to PDB code: 
Top Page protein links
Plant protein PDB id
Protein chain
48 a.a. *
* Residue conservation analysis

References listed in PDB file
Key reference
Title Accurate protein crystallography at ultra-High resolution: valence electron distribution in crambin.
Authors C.Jelsch, M.M.Teeter, V.Lamzin, V.Pichon-Pesme, R.H.Blessing, C.Lecomte.
Ref. Proc Natl Acad Sci U S A, 2000, 97, 3171-3176. [DOI no: 10.1073/pnas.97.7.3171]
PubMed id 10737790
The charge density distribution of a protein has been refined experimentally. Diffraction data for a crambin crystal were measured to ultra-high resolution (0.54 A) at low temperature by using short-wavelength synchrotron radiation. The crystal structure was refined with a model for charged, nonspherical, multipolar atoms to accurately describe the molecular electron density distribution. The refined parameters agree within 25% with our transferable electron density library derived from accurate single crystal diffraction analyses of several amino acids and small peptides. The resulting electron density maps of redistributed valence electrons (deformation maps) compare quantitatively well with a high-level quantum mechanical calculation performed on a monopeptide. This study provides validation for experimentally derived parameters and a window into charge density analysis of biological macromolecules.
Figure 1.
Fig. 1. Ribbon diagram (16) showing the general fold of crambin. The disulfide bridges are shown in yellow. -sheet and extended chain are shown in green and the helices are red.
Figure 2.
Fig. 2. Residual electron density in the peptide bond plane. (A) For the peptide Ala-9-Arg-10 when using a spherical neutral atom model, contour level 0.05 e^ /Å3. (B) Averaged over the 34 nondisordered peptides in crambin when using a spherical neutral atom model. (C) When using a multipolar charged atom model transferred from the database and (D) with average valence populations and multipoles refined, contour level 0.02 e^ /Å3. Positive: red lines; negative: blue lines.
Go to PROCHECK summary