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2j2z
From Proteopedia
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==Overview== | ==Overview== | ||
| - | P pili are important adhesive fibres that are assembled by the conserved | + | P pili are important adhesive fibres that are assembled by the conserved chaperone-usher pathway. During pilus assembly, the subunits are incorporated into the growing fibre by the donor-strand exchange mechanism, whereby the beta-strand of the chaperone, which complements the incomplete immunoglobulin fold of each subunit, is displaced by the amino-terminal extension of an incoming subunit in a zip-in-zip-out exchange process that is initiated at the P5 pocket, an exposed hydrophobic pocket in the groove of the subunit. In vivo, termination of P pilus growth requires a specialized subunit, PapH. Here, we show that PapH is incorporated at the base of the growing pilus, where it is unable to undergo donor-strand exchange. This inability is not due to a stronger PapD-PapH interaction, but to a lack of a P5 initiator pocket in the PapH structure, suggesting that PapH terminates pilus growth because it is lacking the initiation point by which donor-strand exchange proceeds. |
==About this Structure== | ==About this Structure== | ||
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[[Category: pilus termination]] | [[Category: pilus termination]] | ||
| - | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 17:58:41 2008'' |
Revision as of 15:58, 21 February 2008
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X-RAY STRUCTURE OF THE CHAPERONE PAPD IN COMPLEX WITH THE PILUS TERMINATOR SUBUNIT PAPH AT 2.3 ANGSTROM RESOLUTION
Overview
P pili are important adhesive fibres that are assembled by the conserved chaperone-usher pathway. During pilus assembly, the subunits are incorporated into the growing fibre by the donor-strand exchange mechanism, whereby the beta-strand of the chaperone, which complements the incomplete immunoglobulin fold of each subunit, is displaced by the amino-terminal extension of an incoming subunit in a zip-in-zip-out exchange process that is initiated at the P5 pocket, an exposed hydrophobic pocket in the groove of the subunit. In vivo, termination of P pilus growth requires a specialized subunit, PapH. Here, we show that PapH is incorporated at the base of the growing pilus, where it is unable to undergo donor-strand exchange. This inability is not due to a stronger PapD-PapH interaction, but to a lack of a P5 initiator pocket in the PapH structure, suggesting that PapH terminates pilus growth because it is lacking the initiation point by which donor-strand exchange proceeds.
About this Structure
2J2Z is a Protein complex structure of sequences from Escherichia coli with and as ligands. Known structural/functional Site: . Full crystallographic information is available from OCA.
Reference
Molecular mechanism of P pilus termination in uropathogenic Escherichia coli., Verger D, Miller E, Remaut H, Waksman G, Hultgren S, EMBO Rep. 2006 Dec;7(12):1228-32. Epub 2006 Nov 3. PMID:17082819
Page seeded by OCA on Thu Feb 21 17:58:41 2008
