1cm4: Difference between revisions
From Proteopedia
Jump to navigationJump to search
No edit summary |
No edit summary |
||
| Line 4: | Line 4: | ||
|PDB= 1cm4 |SIZE=350|CAPTION= <scene name='initialview01'>1cm4</scene>, resolution 2.0Å | |PDB= 1cm4 |SIZE=350|CAPTION= <scene name='initialview01'>1cm4</scene>, resolution 2.0Å | ||
|SITE= | |SITE= | ||
|LIGAND= <scene name='pdbligand=CA:CALCIUM ION'>CA</scene> | |LIGAND= <scene name='pdbligand=CA:CALCIUM+ION'>CA</scene> | ||
|ACTIVITY= [http://en.wikipedia.org/wiki/Calcium/calmodulin-dependent_protein_kinase Calcium/calmodulin-dependent protein kinase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=2.7.11.17 2.7.11.17] | |ACTIVITY= <span class='plainlinks'>[http://en.wikipedia.org/wiki/Calcium/calmodulin-dependent_protein_kinase Calcium/calmodulin-dependent protein kinase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=2.7.11.17 2.7.11.17] </span> | ||
|GENE= | |GENE= | ||
|DOMAIN= | |||
|RELATEDENTRY= | |||
|RESOURCES=<span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1cm4 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1cm4 OCA], [http://www.ebi.ac.uk/pdbsum/1cm4 PDBsum], [http://www.rcsb.org/pdb/explore.do?structureId=1cm4 RCSB]</span> | |||
}} | }} | ||
| Line 14: | Line 17: | ||
==Overview== | ==Overview== | ||
BACKGROUND: Calmodulin is a calcium-activated regulatory protein which can bind to many different targets. The protein resembles a highly flexible dumbbell, and bends in the middle as it binds. This and other motions must be understood to formulate a realistic model of calmodulin function. RESULTS: Using the Bragg reflections from X-ray crystallography, a multiple-conformer refinement of a calmodulin-peptide complex shows anisotropic displacements, with high variations of dihedral angles in several nonhelical domains: the flexible linker; three of the four calcium-binding sites (including both of the N-terminal sites); and a turn connecting the C-terminal EF-hand calcium-binding domains. Three-dimensional maps of the large scale diffuse X-ray scattering data show isotropic liquid-like motions with an unusually small correlation length. Three-dimensional maps of the small scale diffuse streaks show highly coupled, anisotropic motions along the head-to-tail molecular packing direction in the unit cell. There is also weak coupling perpendicular to the head-to-tail packing direction, particularly across a cavity occupied by the disordered linker domain of the molecule. CONCLUSIONS: Together, the Bragg and diffuse scattering present a self-consistent description of the motions in the flexible linker of calmodulin. The other mobile regions of the protein are also of great interest. In particular, the high variations in the calcium-binding sites are likely to influence how strongly they bind ions. This is especially important in the N-terminal sites, which regulate the activity of the molecule. | BACKGROUND: Calmodulin is a calcium-activated regulatory protein which can bind to many different targets. The protein resembles a highly flexible dumbbell, and bends in the middle as it binds. This and other motions must be understood to formulate a realistic model of calmodulin function. RESULTS: Using the Bragg reflections from X-ray crystallography, a multiple-conformer refinement of a calmodulin-peptide complex shows anisotropic displacements, with high variations of dihedral angles in several nonhelical domains: the flexible linker; three of the four calcium-binding sites (including both of the N-terminal sites); and a turn connecting the C-terminal EF-hand calcium-binding domains. Three-dimensional maps of the large scale diffuse X-ray scattering data show isotropic liquid-like motions with an unusually small correlation length. Three-dimensional maps of the small scale diffuse streaks show highly coupled, anisotropic motions along the head-to-tail molecular packing direction in the unit cell. There is also weak coupling perpendicular to the head-to-tail packing direction, particularly across a cavity occupied by the disordered linker domain of the molecule. CONCLUSIONS: Together, the Bragg and diffuse scattering present a self-consistent description of the motions in the flexible linker of calmodulin. The other mobile regions of the protein are also of great interest. In particular, the high variations in the calcium-binding sites are likely to influence how strongly they bind ions. This is especially important in the N-terminal sites, which regulate the activity of the molecule. | ||
==About this Structure== | ==About this Structure== | ||
| Line 28: | Line 28: | ||
[[Category: Jr., G N.Phillips.]] | [[Category: Jr., G N.Phillips.]] | ||
[[Category: Wall, M E.]] | [[Category: Wall, M E.]] | ||
[[Category: complex (calcium-binding/transferase)]] | [[Category: complex (calcium-binding/transferase)]] | ||
[[Category: ef-hand calcium-binding protein]] | [[Category: ef-hand calcium-binding protein]] | ||
''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Sun Mar 30 19:24:19 2008'' | ||
