3BFW: Crystal Structure Of Truncated Fimg (fimgt) In Complex With The Donor Strand Peptide Of Fimf (dsf)

Adhesive type 1 pili from uropathogenic Escherichia coli strains are heat and denaturant resistant, filamentous protein complexes. Individual pilus subunits associate through "donor strand complementation," whereby the incomplete immunoglobulin-like fold of each subunit is completed by the N-terminal extension of a neighboring subunit. We show that antiparallel donor strand insertion generally causes nonequilibrium behavior in protein folding and extreme activation energy barriers for dissociation of subunit-subunit complexes. We identify the most kinetically stable, noncovalent protein complex known to date. The complex between the pilus subunit FimG and the donor strand peptide of the subunit FimF shows an extrapolated dissociation half-life of 3 x 10(9) years. The 15 residue peptide forms ideal intermolecular beta sheet H-bonds with FimG over 10 residues, and its hydrophobic side chains strongly interact with the hydrophobic core of FimG. The results show that kinetic stability and nonequilibrium behavior in protein folding confers infinite stability against dissociation in extracellular protein complexes.
PDB ID: 3BFWDownload
MMDB ID: 62841
PDB Deposition Date: 2007/11/23
Updated in MMDB: 2011/05
Experimental Method:
x-ray diffraction
Resolution: 1.8  Å
Source Organism:
Escherichia coli str. K-12 substr. W3110
Similar Structures:
Biological Unit for 3BFW: dimeric; determined by author and by software (PISA)
Molecular Components in 3BFW
Label Count Molecule
Proteins (2 molecules)
Protein Fimg(Gene symbol: fimG)
Molecule annotation
Protein Fimf(Gene symbol: fimF)
Molecule annotation
Chemical (1 molecule)
* Click molecule labels to explore molecular sequence information.

Citing MMDB