1t92
From Proteopedia
(New page: 200px<br /><applet load="1t92" size="450" color="white" frame="true" align="right" spinBox="true" caption="1t92, resolution 1.60Å" /> '''Crystal structure of...) |
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| - | [[Image:1t92.gif|left|200px]]<br /><applet load="1t92" size=" | + | [[Image:1t92.gif|left|200px]]<br /><applet load="1t92" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="1t92, resolution 1.60Å" /> | caption="1t92, resolution 1.60Å" /> | ||
'''Crystal structure of N-terminal truncated pseudopilin PulG'''<br /> | '''Crystal structure of N-terminal truncated pseudopilin PulG'''<br /> | ||
==Overview== | ==Overview== | ||
| - | The pseudopilin PulG is one of several essential components of the type II | + | The pseudopilin PulG is one of several essential components of the type II pullulanase secretion machinery (the Pul secreton) of the Gram-negative bacterium Klebsiella oxytoca. The sequence of the N-terminal 25 amino acids of the PulG precursor is hydrophobic and very similar to the corresponding region of type IV pilins. The structure of a truncated PulG (lacking the homologous region), as determined by X-ray crystallography, was found to include part of the long N-terminal alpha-helix and the four internal anti-parallel beta-strands that characterize type IV pilins, but PulG lacks the highly variable loop region with a disulphide bond that is found in the latter. When overproduced, PulG forms flexible pili whose structural features, as visualized by electron microscopy, are similar to those of bacterial type IV pili. The average helical repeat comprises 17 PulG subunits and four helical turns. Electron microscopy and molecular modelling show that PulG probably assembles into left-handed helical pili with the long N-terminal alpha-helix tightly packed in the centre of the pilus. As in the type IV pilins, the hydrophobic N-terminal part of the PulG alpha-helix is necessary for its assembly. Subtle sequence variations within this highly conserved segment seem to determine whether or not a type IV pilin can be assembled into pili by the Pul secreton. |
==About this Structure== | ==About this Structure== | ||
| - | 1T92 is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Klebsiella_pneumoniae Klebsiella pneumoniae] with ZN as [http://en.wikipedia.org/wiki/ligand ligand]. Full crystallographic information is available from [http:// | + | 1T92 is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Klebsiella_pneumoniae Klebsiella pneumoniae] with <scene name='pdbligand=ZN:'>ZN</scene> as [http://en.wikipedia.org/wiki/ligand ligand]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1T92 OCA]. |
==Reference== | ==Reference== | ||
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[[Category: Mueller, S.]] | [[Category: Mueller, S.]] | ||
[[Category: Philippsen, A.]] | [[Category: Philippsen, A.]] | ||
| - | [[Category: Pugsley, A | + | [[Category: Pugsley, A P.]] |
[[Category: Ringler, P.]] | [[Category: Ringler, P.]] | ||
[[Category: Schaefer, K.]] | [[Category: Schaefer, K.]] | ||
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[[Category: zinc]] | [[Category: zinc]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 15:11:11 2008'' |
Revision as of 13:11, 21 February 2008
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Crystal structure of N-terminal truncated pseudopilin PulG
Overview
The pseudopilin PulG is one of several essential components of the type II pullulanase secretion machinery (the Pul secreton) of the Gram-negative bacterium Klebsiella oxytoca. The sequence of the N-terminal 25 amino acids of the PulG precursor is hydrophobic and very similar to the corresponding region of type IV pilins. The structure of a truncated PulG (lacking the homologous region), as determined by X-ray crystallography, was found to include part of the long N-terminal alpha-helix and the four internal anti-parallel beta-strands that characterize type IV pilins, but PulG lacks the highly variable loop region with a disulphide bond that is found in the latter. When overproduced, PulG forms flexible pili whose structural features, as visualized by electron microscopy, are similar to those of bacterial type IV pili. The average helical repeat comprises 17 PulG subunits and four helical turns. Electron microscopy and molecular modelling show that PulG probably assembles into left-handed helical pili with the long N-terminal alpha-helix tightly packed in the centre of the pilus. As in the type IV pilins, the hydrophobic N-terminal part of the PulG alpha-helix is necessary for its assembly. Subtle sequence variations within this highly conserved segment seem to determine whether or not a type IV pilin can be assembled into pili by the Pul secreton.
About this Structure
1T92 is a Single protein structure of sequence from Klebsiella pneumoniae with as ligand. Full crystallographic information is available from OCA.
Reference
Structure and assembly of the pseudopilin PulG., Kohler R, Schafer K, Muller S, Vignon G, Diederichs K, Philippsen A, Ringler P, Pugsley AP, Engel A, Welte W, Mol Microbiol. 2004 Nov;54(3):647-64. PMID:15491357
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