P53R2: Difference between revisions
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<scene name='Sandbox156/Iron-binding_site/2'>An iron-binding site</scene> is highlighted. But concerning this site, the two monomers are not the same. Actually, the B monomer has two iron-binding site (called Fe2 and Fe1) whereas the A monomer has only one which is Fe2. This can be explained by structural changes in the helix that compose the two monomers. The 37 to 42 N-terminal residues (called the swivel loop) from one monomer can rotate between two conformations and can influence the position of the helix B or D on the opposite monomer. | <scene name='Sandbox156/Iron-binding_site/2'>An iron-binding site</scene> is highlighted. But concerning this site, the two monomers are not the same. Actually, the B monomer has two iron-binding site (called Fe2 and Fe1) whereas the A monomer has only one which is Fe2. This can be explained by structural changes in the helix that compose the two monomers. The 37 to 42 N-terminal residues (called the swivel loop) from one monomer can rotate between two conformations and can influence the position of the helix B or D on the opposite monomer. | ||
[[Image:Thetwomonomers.jpg| thumb | 400px | Figure 1: The structure of the p53R2 protein is shown. P53R2 is built up by two monomers A and B, which contain several iron-binding sites.]] | [[Image:Thetwomonomers.jpg| thumb | center | 400px | Figure 1: The structure of the p53R2 protein is shown. P53R2 is built up by two monomers A and B, which contain several iron-binding sites.]] | ||
The N-terminal residues of the monomer A can stabilize the B helix of the monomer B due to different interactions. R41 of the monomer A forms a salt bridge with E119 of monomer A. This interaction permits the formation of a H-bond between R40 of monomer A with G101of monomer B. Furthermore K37 in monomer A forms a salt bridge with E105 of monomer B and this stabilize its B helix. All the interactions allow D100 of monomer B to be well oriented to bind Fe1 (see Figure 2, Smith P. et al., <ref>PMID:19728742</ref>). | The N-terminal residues of the monomer A can stabilize the B helix of the monomer B due to different interactions. R41 of the monomer A forms a salt bridge with E119 of monomer A. This interaction permits the formation of a H-bond between R40 of monomer A with G101of monomer B. Furthermore K37 in monomer A forms a salt bridge with E105 of monomer B and this stabilize its B helix. All the interactions allow D100 of monomer B to be well oriented to bind Fe1 (see Figure 2, Smith P. et al., <ref>PMID:19728742</ref>). | ||