2Y1V: Full Length Structure Of Rrgb Pilus Protein From Streptococcus Pneumoniae

RrgB is the major pilin which forms the pneumococcal pilus backbone. We report the high-resolution crystal structure of the full-length form of RrgB containing the IPQTG sorting motif. The RrgB fold is organized into four distinct domains, D1-D4, each of which is stabilized by an isopeptide bond. Crystal packing revealed a head-to-tail organization involving the interaction of the IPQTG motif into the D1 domain of two successive RrgB monomers. This fibrillar assembly, which fits into the electron microscopy density map of the native pilus, probably induces the formation of the D1 isopeptide bond as observed for the first time in the present study, since neither in published structures nor in soluble RrgB produced in Escherichia coli or in Streptococcus pneumoniae is the D1 bond present. Experiments performed in live bacteria confirmed that the intermolecular bond linking the RrgB subunits takes place between the IPQTG motif of one RrgB subunit and the Lys183 pilin motif residue of an adjacent RrgB subunit. In addition, we present data indicating that the D1 isopeptide bond is involved in RrgB stabilization. In conclusion, the crystal RrgB fibre is a compelling model for deciphering the molecular details required to generate the pneumococcal pilus.
PDB ID: 2Y1VDownload
MMDB ID: 94870
PDB Deposition Date: 2010/12/10
Updated in MMDB: 2011/11
Experimental Method:
x-ray diffraction
Resolution: 2.39  Å
Source Organism:
Similar Structures:
Biological Unit for 2Y1V: monomeric; determined by author and by software (PISA)
Molecular Components in 2Y1V
Label Count Molecule
Protein (1 molecule)
Cell Wall Surface Anchor Family Protein
Molecule annotation
Chemicals (3 molecules)
* Click molecule labels to explore molecular sequence information.

Citing MMDB