1JW8

1.3 ANGSTROM RESOLUTION CRYSTAL STRUCTURE OF P6 FORM OF MYOGLOBIN

Summary for 1JW8

• Entry DOI: 10.2210/pdb1jw8/pdb
• Related: 2MBW
• Descriptor: MYOGLOBIN, SULFATE ION, PROTOPORPHYRIN IX CONTAINING FE, ... (5 entities in total)
• Functional Keywords: anisotropic refinement myoglobin, oxygen storage-transport complex, oxygen storage/transport
• Biological source: Physeter catodon (sperm whale)
• Total number of polymer chains: 1
• Total formula weight: 18297.85

Authors

Phillips Jr., G.N. (deposition date: 2001-09-03, release date: 2001-10-10, Last modification date: 2024-02-07)

Primary citation

Kondrashov, D.A.,Zhang, W.,Aranda, R.,Stec, B.,Phillips Jr., G.N.
Sampling of the native conformational ensemble of myoglobin via structures in different crystalline environments.
Proteins, 70:353-362, 2008

PubMed Abstract: Proteins sample multiple conformational substates in their native environment, but the process of crystallization selects the conformers that allow for close packing. The population of conformers can be shifted by varying the environment through a range of crystallization conditions, often resulting in different space groups and changes in the packing arrangements. Three high resolution structures of myoglobin (Mb) in different crystal space groups are presented, including one in a new space group P6(1)22 and two structures in space groups P2(1)2(1)2(1) and P6. We compare coordinates and anisotropic displacement parameters (ADPs) from these three structures plus an existing structure in space group P2(1). While the overall changes are small, there is substantial variation in several external regions with varying patterns of crystal contacts across the space group packing arrangements. The structural ensemble containing four different crystal forms displays greater conformational variance (Calpha rmsd of 0.54-0.79 A) in comparison to a collection of four Mb structures with different ligands and mutations in the same crystal form (Calpha rmsd values of 0.28-0.37 A). The high resolution of the data enables comparison of both the magnitudes and directions of ADPs, which are found to be suppressed by crystal contacts. A composite dynamic profile of Mb structural variation from the four structures was compared with an independent structural ensemble developed from NMR refinement. Despite the limitations and biases of each method, the ADPs of the crystallographic ensemble closely match the positional variance from the solution NMR ensemble with linear correlation of 0.8. This suggests that crystal packing selects conformers representative of the solution ensemble, and several different crystal forms give a more complete view of the plasticity of a protein structure.

PubMed: 17680690
DOI: 10.1002/prot.21499

Experimental method

X-RAY DIFFRACTION (1.3 Å)