6JCH

Crystal structure of SpaE basal pilin from Lactobacillus rhamnosus GG - Orthorhombic form

Summary for 6JCH

• Entry DOI: 10.2210/pdb6jch/pdb
• Related: 6JBV 6JK7
• Descriptor: Pilus assembly protein, SODIUM ION (3 entities in total)
• Functional Keywords: basal pilins, spafed pilus, isopeptide bonds, pilus anchoring, surface proteins, probiotic, sortase, cell adhesion
• Biological source: Lactobacillus rhamnosus GG
• Total number of polymer chains: 1
• Total formula weight: 44902.87

Authors

Megta, A.K.,Mishra, A.K.,Palva, A.,von Ossowski, I.,Krishnan, V. (deposition date: 2019-01-28, release date: 2019-06-26, Last modification date: 2024-10-23)

Primary citation

Megta, A.K.,Mishra, A.K.,Palva, A.,von Ossowski, I.,Krishnan, V.
Crystal structure of basal pilin SpaE reveals the molecular basis of its incorporation in the lactobacillar SpaFED pilus.
J.Struct.Biol., 207:74-84, 2019

PubMed Abstract: For some Gram-positive genera and species, the long-extended and adhesive sortase-dependent pilus plays an essential role during host colonization, biofilm formation, and immune modulation. Lactobacillus rhamnosus GG is a gut-adapted commensal strain that harbors the operonic genes for the SpaCBA and SpaFED pili, both being comprised of three different protein subunits termed the backbone, tip, and basal pilins. Crystal structures of the backbone pilins (SpaA and SpaD) have recently been solved, and here we describe the high-resolution (1.5 Å) structural determination of the SpaE basal pilin. SpaE consists of two immunoglobulin-like CnaB domains, with each displaying a spontaneously formed internal isopeptide bond, though apparently slow forming in the N-terminal domain. Remarkably, SpaE contains an atypically lengthy unstructured C-terminal tail, along with an YPKN pilin motif peptide, which is normally reserved for backbone subunits. Based on our analysis of the crystal structure data, we provide a molecular model for the basal positioning of the SpaE pilin within the SpaFED pilus.

PubMed: 31026587
DOI: 10.1016/j.jsb.2019.04.016

Experimental method

X-RAY DIFFRACTION (1.536 Å)