1rcg
From Proteopedia
| Line 1: | Line 1: | ||
[[Image:1rcg.gif|left|200px]] | [[Image:1rcg.gif|left|200px]] | ||
| - | + | <!-- | |
| - | + | The line below this paragraph, containing "STRUCTURE_1rcg", creates the "Structure Box" on the page. | |
| - | + | You may change the PDB parameter (which sets the PDB file loaded into the applet) | |
| - | + | or the SCENE parameter (which sets the initial scene displayed when the page is loaded), | |
| - | + | or leave the SCENE parameter empty for the default display. | |
| - | + | --> | |
| - | + | {{STRUCTURE_1rcg| PDB=1rcg | SCENE= }} | |
| - | | | + | |
| - | | | + | |
| - | }} | + | |
'''BULLFROG RED CELL L FERRITIN SULFATE/MN/PH 6.3''' | '''BULLFROG RED CELL L FERRITIN SULFATE/MN/PH 6.3''' | ||
| Line 28: | Line 25: | ||
[[Category: Theil, E C.]] | [[Category: Theil, E C.]] | ||
[[Category: Trikha, J.]] | [[Category: Trikha, J.]] | ||
| - | [[Category: | + | [[Category: Iron storage]] |
| - | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Sat May 3 07:19:54 2008'' | |
| - | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on | + | |
Revision as of 04:19, 3 May 2008
BULLFROG RED CELL L FERRITIN SULFATE/MN/PH 6.3
Overview
Ferritin is a highly conserved multisubunit protein in animals, plants and microbes which assembles with cubic symmetry and transports hydrated iron ions and protons to and from a mineralized core in the protein interior. We report here the high resolution structures of recombinant amphibian red-cell L ferritin and two mutants solved under two sets of conditions. In one mutant, Glu56, 57, 58 and 60 were replaced with Ala, producing a lag phase in the kinetics of iron uptake. In the second mutant, His25 was replaced with Tyr with, at most, subtle effects on function. A molecule of betaine, used in the purification, is bound in all structures at the 2-fold axis near the recently identified heme binding site of bacterioferritin and horse spleen L ferritin. Comparisons of the five amphibian structures identify two regions of the molecule in which conformational flexibility may be related to function. The positions and interactions of a set of 10 to 18 side-chains, most of which are on the inner surface of the protein, are sensitive both to solution conditions and to the Glu-->Ala mutation. A subset of these side-chains and a chain of ordered solvent molecules extends from the vicinity of Glu56 to 58 and Glu60 to the 3-fold channel in the wild type protein and may be involved in the transport of either iron or protons. The "spine of hydration" is disrupted in the Glu-->Ala mutant. In contrast, H25Y mutation shifts the positions of backbone atoms between the site of the mutation and the 4-fold axis and side-chain positions throughout the structure; the largest changes in the position of backbone atoms are in the DE loop and E helix, approximately 10 A from the mutation site. In combination, these results indicate that solvation, structural plasticity and cooperative structural changes may play a role in ferritin function. Analogies with the structure and function of ion channel proteins such as annexins are noted.
About this Structure
1RCG is a Single protein structure of sequence from Rana catesbeiana. Full crystallographic information is available from OCA.
Reference
High resolution crystal structures of amphibian red-cell L ferritin: potential roles for structural plasticity and solvation in function., Trikha J, Theil EC, Allewell NM, J Mol Biol. 1995 May 19;248(5):949-67. PMID:7760335 Page seeded by OCA on Sat May 3 07:19:54 2008
