1z15
From Proteopedia
(New page: 200px<br /><applet load="1z15" size="450" color="white" frame="true" align="right" spinBox="true" caption="1z15, resolution 1.70Å" /> '''Crystal structure an...) |
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| - | [[Image:1z15.gif|left|200px]]<br /><applet load="1z15" size=" | + | [[Image:1z15.gif|left|200px]]<br /><applet load="1z15" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="1z15, resolution 1.70Å" /> | caption="1z15, resolution 1.70Å" /> | ||
'''Crystal structure analysis of periplasmic Leu/Ile/Val-binding protein in superopen form'''<br /> | '''Crystal structure analysis of periplasmic Leu/Ile/Val-binding protein in superopen form'''<br /> | ||
==Overview== | ==Overview== | ||
| - | The leucine/isoleucine/valine-binding protein (LIVBP or LivJ) serves as | + | The leucine/isoleucine/valine-binding protein (LIVBP or LivJ) serves as the primary high-affinity receptor of the Escherichia coli ABC-type transporter for the three aliphatic amino acids. The first structure of LIVBP determined previously without bound ligand showed a molecule comprised of two domains which are far apart and bisected by a wide open, solvent-accessible cleft. Here we report the crystal structures of another ligand-free state and three complexes with the aliphatic amino acids. In the present ligand-free structure, the two domains are farther apart. In the three very similar complex structures, the two domains are in close proximity, and each desolvated ligand is completely engulfed in the cleft and bound by both domains. The two different ligand-free structures, combined with those of the very similar ligand-bound structures, indicate the trajectory and backbone torsion angle changes of the hinges that accompany domain closure and play crucial functional roles. The amino acids are bound by polar and nonpolar interactions, occurring predominantly in one domain. Consistent with the protein specificity, the aliphatic side chains of the ligands lie in a hydrophobic pocket fully formed following domain or cleft closure. Comparison of the structures of LIVBP with several different binding proteins indicates no correlations between the magnitudes of the hinge-bending angles and the protein masses, the ligand sizes, or the number of segments connecting the two domains. Results of normal-mode analysis and molecular dynamics simulations are consistent with the trajectory and intrinsic flexibility of the interdomain hinges and the dominance of one domain in ligand binding in the open state. |
==About this Structure== | ==About this Structure== | ||
| - | 1Z15 is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Escherichia_coli Escherichia coli]. Full crystallographic information is available from [http:// | + | 1Z15 is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Escherichia_coli Escherichia coli]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1Z15 OCA]. |
==Reference== | ==Reference== | ||
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[[Category: Escherichia coli]] | [[Category: Escherichia coli]] | ||
[[Category: Single protein]] | [[Category: Single protein]] | ||
| - | [[Category: Kristensen, D | + | [[Category: Kristensen, D M.]] |
[[Category: Ma, J.]] | [[Category: Ma, J.]] | ||
| - | [[Category: Quiocho, F | + | [[Category: Quiocho, F A.]] |
| - | [[Category: Trakhanov, S | + | [[Category: Trakhanov, S D.]] |
| - | [[Category: Vyas, N | + | [[Category: Vyas, N K.]] |
[[Category: aliphatic amino acid binding protein]] | [[Category: aliphatic amino acid binding protein]] | ||
[[Category: alpha-beta fold]] | [[Category: alpha-beta fold]] | ||
[[Category: periplasmic binding proteins]] | [[Category: periplasmic binding proteins]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 16:11:09 2008'' |
Revision as of 14:11, 21 February 2008
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Crystal structure analysis of periplasmic Leu/Ile/Val-binding protein in superopen form
Overview
The leucine/isoleucine/valine-binding protein (LIVBP or LivJ) serves as the primary high-affinity receptor of the Escherichia coli ABC-type transporter for the three aliphatic amino acids. The first structure of LIVBP determined previously without bound ligand showed a molecule comprised of two domains which are far apart and bisected by a wide open, solvent-accessible cleft. Here we report the crystal structures of another ligand-free state and three complexes with the aliphatic amino acids. In the present ligand-free structure, the two domains are farther apart. In the three very similar complex structures, the two domains are in close proximity, and each desolvated ligand is completely engulfed in the cleft and bound by both domains. The two different ligand-free structures, combined with those of the very similar ligand-bound structures, indicate the trajectory and backbone torsion angle changes of the hinges that accompany domain closure and play crucial functional roles. The amino acids are bound by polar and nonpolar interactions, occurring predominantly in one domain. Consistent with the protein specificity, the aliphatic side chains of the ligands lie in a hydrophobic pocket fully formed following domain or cleft closure. Comparison of the structures of LIVBP with several different binding proteins indicates no correlations between the magnitudes of the hinge-bending angles and the protein masses, the ligand sizes, or the number of segments connecting the two domains. Results of normal-mode analysis and molecular dynamics simulations are consistent with the trajectory and intrinsic flexibility of the interdomain hinges and the dominance of one domain in ligand binding in the open state.
About this Structure
1Z15 is a Single protein structure of sequence from Escherichia coli. Full crystallographic information is available from OCA.
Reference
Ligand-free and -bound structures of the binding protein (LivJ) of the Escherichia coli ABC leucine/isoleucine/valine transport system: trajectory and dynamics of the interdomain rotation and ligand specificity., Trakhanov S, Vyas NK, Luecke H, Kristensen DM, Ma J, Quiocho FA, Biochemistry. 2005 May 3;44(17):6597-608. PMID:15850393
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