1i3r
From Proteopedia
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==Overview== | ==Overview== | ||
| - | IE/DR MHC class II molecules have an extensive H-bonding network under the | + | IE/DR MHC class II molecules have an extensive H-bonding network under the bound peptide. In IE(k), two alpha chain acidic amino acids in the core of this network were mutated to amides. At low pH, the mutant molecule exchanged peptide much more rapidly than the wild-type. The crystal structure of the mutant IE(k) revealed the loss of a single buried water molecule and a reorganization of the predicted H-bonding network. We suggest that these mutations enhance the transition of MHC class II to an open conformation at low pH allowing the bound peptide to escape. In wild-type IE(k), the need to protonate these amino acids also may be a bottleneck in the return to a closed conformation after peptide binding. |
==About this Structure== | ==About this Structure== | ||
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[[Category: Mus musculus]] | [[Category: Mus musculus]] | ||
[[Category: Protein complex]] | [[Category: Protein complex]] | ||
| - | [[Category: Kappler, J | + | [[Category: Kappler, J W.]] |
[[Category: Wilson, N.]] | [[Category: Wilson, N.]] | ||
[[Category: NAG]] | [[Category: NAG]] | ||
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[[Category: peptide]] | [[Category: peptide]] | ||
| - | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 13:07:45 2008'' |
Revision as of 11:07, 21 February 2008
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CRYSTAL STRUCTURE OF A MUTANT IEK CLASS II MHC MOLECULE
Overview
IE/DR MHC class II molecules have an extensive H-bonding network under the bound peptide. In IE(k), two alpha chain acidic amino acids in the core of this network were mutated to amides. At low pH, the mutant molecule exchanged peptide much more rapidly than the wild-type. The crystal structure of the mutant IE(k) revealed the loss of a single buried water molecule and a reorganization of the predicted H-bonding network. We suggest that these mutations enhance the transition of MHC class II to an open conformation at low pH allowing the bound peptide to escape. In wild-type IE(k), the need to protonate these amino acids also may be a bottleneck in the return to a closed conformation after peptide binding.
About this Structure
1I3R is a Protein complex structure of sequences from Mus musculus with and as ligands. Full crystallographic information is available from OCA.
Reference
Mutations changing the kinetics of class II MHC peptide exchange., Wilson N, Fremont D, Marrack P, Kappler J, Immunity. 2001 May;14(5):513-22. PMID:11371354
Page seeded by OCA on Thu Feb 21 13:07:45 2008
Categories: Mus musculus | Protein complex | Kappler, J W. | Wilson, N. | NAG | NDG | Mhc classii | Peptide
