1RWY: Crystal Structure Of Rat Alpha-parvalbumin At 1.05 Resolution

Citation:
Abstract
The crystal structure of rat alpha-parvalbumin has been determined at 1.05 Angstrom resolution, using synchrotron data collected at Advanced Photon Source beamline 19-ID. After refinement with SHELX, employing anisotropic displacement parameters and riding hydrogen atoms, R = 0.132 and R(free) = 0.162. The average coordinate estimated standard deviations are 0.021 Angstrom and 0.038 Angstrom for backbone atoms and side-chain atoms, respectively. Besides providing a more precise view of the alpha-isoform than previously available, these data permit comparison with the 0.91 Angstrom structure determined for pike beta-parvalbumin. Visualization of the anisotropic displacement parameters as thermal ellipsoids yields insight into the atomic motion within the Ca(2+)-binding sites. The asymmetric unit includes three parvalbumin (PV) molecules. Interestingly, the EF site in one displays uncharacteristic flexibility. The ellipsoids for Asp-92 are particularly large and non-spherical, and the shape of the Ca(2+) ellipsoid implies significant vibrational motion perpendicular to the plane defined by the four y and z ligands. The relative dearth of crystal-packing interactions in this site suggests that the heightened flexibility may be the result of diminished intermolecular contacts. The implication is that, by impeding conformational mobility, crystal-packing forces may cause serious overestimation of EF-hand rigidity. The high quality of the data permitted 11 residues to be modeled in alternative side-chain conformations, including the two core residues, Ile-97 and Leu-105. The discrete disorder observed for Ile-97 may have functional ramifications, providing a mechanism for communicating binding status between the CD and EF binding loops and between the PV metal ion-binding domain and the N-terminal AB region.
PDB ID: 1RWYDownload
MMDB ID: 27762
PDB Deposition Date: 2003/12/17
Updated in MMDB: 2017/11
Experimental Method:
x-ray diffraction
Resolution: 1.05  Å
Source Organism:
Similar Structures:
Biological Unit for 1RWY: monomeric; determined by author
Molecular Components in 1RWY
Label Count Molecule
Protein (1 molecule)
1
Parvalbumin Alpha(Gene symbol: Pvalb)
Molecule annotation
Chemicals (4 molecules)
1
2
2
1
3
1
* Click molecule labels to explore molecular sequence information.

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