1qvp
From Proteopedia
(New page: 200px<br /><applet load="1qvp" size="450" color="white" frame="true" align="right" spinBox="true" caption="1qvp" /> '''C terminal SH3-like domain from Diphtheria t...) |
|||
| Line 1: | Line 1: | ||
| - | [[Image:1qvp.gif|left|200px]]<br /><applet load="1qvp" size=" | + | [[Image:1qvp.gif|left|200px]]<br /><applet load="1qvp" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="1qvp" /> | caption="1qvp" /> | ||
'''C terminal SH3-like domain from Diphtheria toxin Repressor residues 144-226.'''<br /> | '''C terminal SH3-like domain from Diphtheria toxin Repressor residues 144-226.'''<br /> | ||
==Overview== | ==Overview== | ||
| - | Diphtheria toxin repressor (DtxR) regulates the expression of | + | Diphtheria toxin repressor (DtxR) regulates the expression of iron-sensitive genes in Corynebacterium diphtheriae, including the diphtheria toxin gene. DtxR contains an N-terminal metal- and DNA-binding domain that is connected by a proline-rich flexible peptide segment (Pr) to a C-terminal src homology 3 (SH3)-like domain. We determined the solution structure of the intramolecular complex formed between the proline-rich segment and the SH3-like domain by use of NMR spectroscopy. The structure of the intramolecularly bound Pr segment differs from that seen in eukaryotic prolylpeptide-SH3 domain complexes. The prolylpeptide ligand is bound by the SH3-like domain in a deep crevice lined by aliphatic amino acid residues and passes through the binding site twice but does not adopt a polyprolyl type-II helix. NMR studies indicate that this intramolecular complex is present in the apo-state of the repressor. Isothermal equilibrium denaturation studies show that intramolecular complex formation contributes to the stability of the apo-repressor. The binding affinity of synthetic peptides to the SH3-like domain was determined using isothermal titration calorimetry. From the structure and the binding energies, we calculated the enhancement in binding energy for the intramolecular reaction and compared it to the energetics of dimerization. Together, the structural and biophysical studies suggest that the proline-rich peptide segment of DtxR functions as a switch that modulates the activation of repressor activity. |
==About this Structure== | ==About this Structure== | ||
| - | 1QVP is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Corynebacterium_diphtheriae Corynebacterium diphtheriae]. Full crystallographic information is available from [http:// | + | 1QVP is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Corynebacterium_diphtheriae Corynebacterium diphtheriae]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1QVP OCA]. |
==Reference== | ==Reference== | ||
| Line 14: | Line 14: | ||
[[Category: Single protein]] | [[Category: Single protein]] | ||
[[Category: Bhattacharya, N.]] | [[Category: Bhattacharya, N.]] | ||
| - | [[Category: Bienkiewicz, E | + | [[Category: Bienkiewicz, E A.]] |
| - | [[Category: Logan, T | + | [[Category: Logan, T M.]] |
| - | [[Category: Love, J | + | [[Category: Love, J F.]] |
[[Category: Marin, V.]] | [[Category: Marin, V.]] | ||
| - | [[Category: Murphy, J | + | [[Category: Murphy, J R.]] |
[[Category: Rangachari, V.]] | [[Category: Rangachari, V.]] | ||
| - | [[Category: Wylie, G | + | [[Category: Wylie, G P.]] |
[[Category: c-terminal domain]] | [[Category: c-terminal domain]] | ||
[[Category: dtxr]] | [[Category: dtxr]] | ||
| Line 29: | Line 29: | ||
[[Category: transcription regulation]] | [[Category: transcription regulation]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 14:44:11 2008'' |
Revision as of 12:44, 21 February 2008
|
C terminal SH3-like domain from Diphtheria toxin Repressor residues 144-226.
Overview
Diphtheria toxin repressor (DtxR) regulates the expression of iron-sensitive genes in Corynebacterium diphtheriae, including the diphtheria toxin gene. DtxR contains an N-terminal metal- and DNA-binding domain that is connected by a proline-rich flexible peptide segment (Pr) to a C-terminal src homology 3 (SH3)-like domain. We determined the solution structure of the intramolecular complex formed between the proline-rich segment and the SH3-like domain by use of NMR spectroscopy. The structure of the intramolecularly bound Pr segment differs from that seen in eukaryotic prolylpeptide-SH3 domain complexes. The prolylpeptide ligand is bound by the SH3-like domain in a deep crevice lined by aliphatic amino acid residues and passes through the binding site twice but does not adopt a polyprolyl type-II helix. NMR studies indicate that this intramolecular complex is present in the apo-state of the repressor. Isothermal equilibrium denaturation studies show that intramolecular complex formation contributes to the stability of the apo-repressor. The binding affinity of synthetic peptides to the SH3-like domain was determined using isothermal titration calorimetry. From the structure and the binding energies, we calculated the enhancement in binding energy for the intramolecular reaction and compared it to the energetics of dimerization. Together, the structural and biophysical studies suggest that the proline-rich peptide segment of DtxR functions as a switch that modulates the activation of repressor activity.
About this Structure
1QVP is a Single protein structure of sequence from Corynebacterium diphtheriae. Full crystallographic information is available from OCA.
Reference
Prolylpeptide binding by the prokaryotic SH3-like domain of the diphtheria toxin repressor: a regulatory switch., Wylie GP, Rangachari V, Bienkiewicz EA, Marin V, Bhattacharya N, Love JF, Murphy JR, Logan TM, Biochemistry. 2005 Jan 11;44(1):40-51. PMID:15628844
Page seeded by OCA on Thu Feb 21 14:44:11 2008
Categories: Corynebacterium diphtheriae | Single protein | Bhattacharya, N. | Bienkiewicz, E A. | Logan, T M. | Love, J F. | Marin, V. | Murphy, J R. | Rangachari, V. | Wylie, G P. | C-terminal domain | Dtxr | Gene regulation | Peptide-binding | Prokaryotic sh3 domain | Repressor | Transcription regulation
