1hz4
From Proteopedia
(New page: 200px<br /><applet load="1hz4" size="450" color="white" frame="true" align="right" spinBox="true" caption="1hz4, resolution 1.45Å" /> '''CRYSTAL STRUCTURE OF...) |
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| - | [[Image:1hz4.jpg|left|200px]]<br /><applet load="1hz4" size=" | + | [[Image:1hz4.jpg|left|200px]]<br /><applet load="1hz4" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="1hz4, resolution 1.45Å" /> | caption="1hz4, resolution 1.45Å" /> | ||
'''CRYSTAL STRUCTURE OF TRANSCRIPTION FACTOR MALT DOMAIN III'''<br /> | '''CRYSTAL STRUCTURE OF TRANSCRIPTION FACTOR MALT DOMAIN III'''<br /> | ||
==Overview== | ==Overview== | ||
| - | BACKGROUND: MalT from Escherichia coli, the best-studied member of the | + | BACKGROUND: MalT from Escherichia coli, the best-studied member of the MalT family of ATP-dependent transcriptional activators, regulates the genes for malto-oligosaccharide utilization. The active form of this 4 domain protein is a homooligomer, and its multimerization is induced by the binding of maltotriose. Domains II and III of MalT were suggested to mediate the oligomerization process, but its molecular mechanism and the specific functions of these domains remain to be identified. RESULTS: We solved the crystal structure of MalT domain III at 1.45 A resolution by multiple isomorphous replacement phasing. The structure reveals eight copies of a two-helix bundle motif arranged in a novel, right-handed superhelix fold with closed walls, followed by a small C-terminal subdomain. The MalT superhelix contains a potential maltotriose binding site and forms a large hydrophobic protein-protein interaction interface that mediates the contact between two MalT domain III molecules. Structure-based analysis of the two-helix bundle motifs revealed a novel degenerated sequence pattern, and repeats of this pattern could be identified in other regulator proteins. CONCLUSIONS: MalT domain III contains a novel superhelix fold. Its protein-protein interaction interface, however, resembles protein binding sites of other superhelical proteins, suggesting a model with domain III mediating MalT oligomerization. Maltotriose seems to modulate the interaction interface and MalT oligomerization by occupying the ligand binding site inside the superhelix. Similar structural and mechanistic features in other MalT protein-family members and unrelated regulator proteins are indicated by the reappearance of a novel sequence motif derived from the MalT domain III structure. |
==About this Structure== | ==About this Structure== | ||
| - | 1HZ4 is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Escherichia_coli Escherichia coli] with SO4, BEZ and GOL as [http://en.wikipedia.org/wiki/ligands ligands]. Full crystallographic information is available from [http:// | + | 1HZ4 is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Escherichia_coli Escherichia coli] with <scene name='pdbligand=SO4:'>SO4</scene>, <scene name='pdbligand=BEZ:'>BEZ</scene> and <scene name='pdbligand=GOL:'>GOL</scene> as [http://en.wikipedia.org/wiki/ligands ligands]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1HZ4 OCA]. |
==Reference== | ==Reference== | ||
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[[Category: two-helix bundles]] | [[Category: two-helix bundles]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 13:06:16 2008'' |
Revision as of 11:06, 21 February 2008
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CRYSTAL STRUCTURE OF TRANSCRIPTION FACTOR MALT DOMAIN III
Overview
BACKGROUND: MalT from Escherichia coli, the best-studied member of the MalT family of ATP-dependent transcriptional activators, regulates the genes for malto-oligosaccharide utilization. The active form of this 4 domain protein is a homooligomer, and its multimerization is induced by the binding of maltotriose. Domains II and III of MalT were suggested to mediate the oligomerization process, but its molecular mechanism and the specific functions of these domains remain to be identified. RESULTS: We solved the crystal structure of MalT domain III at 1.45 A resolution by multiple isomorphous replacement phasing. The structure reveals eight copies of a two-helix bundle motif arranged in a novel, right-handed superhelix fold with closed walls, followed by a small C-terminal subdomain. The MalT superhelix contains a potential maltotriose binding site and forms a large hydrophobic protein-protein interaction interface that mediates the contact between two MalT domain III molecules. Structure-based analysis of the two-helix bundle motifs revealed a novel degenerated sequence pattern, and repeats of this pattern could be identified in other regulator proteins. CONCLUSIONS: MalT domain III contains a novel superhelix fold. Its protein-protein interaction interface, however, resembles protein binding sites of other superhelical proteins, suggesting a model with domain III mediating MalT oligomerization. Maltotriose seems to modulate the interaction interface and MalT oligomerization by occupying the ligand binding site inside the superhelix. Similar structural and mechanistic features in other MalT protein-family members and unrelated regulator proteins are indicated by the reappearance of a novel sequence motif derived from the MalT domain III structure.
About this Structure
1HZ4 is a Single protein structure of sequence from Escherichia coli with , and as ligands. Full crystallographic information is available from OCA.
Reference
Crystal structure of transcription factor MalT domain III: a novel helix repeat fold implicated in regulated oligomerization., Steegborn C, Danot O, Huber R, Clausen T, Structure. 2001 Nov;9(11):1051-60. PMID:11709169
Page seeded by OCA on Thu Feb 21 13:06:16 2008
Categories: Escherichia coli | Single protein | Clausen, T. | Danot, O. | Huber, R. | Steegborn, C. | BEZ | GOL | SO4 | Helix repeats | Protein superhelix | Two-helix bundles
