6EK4

PaxB from Photorhabdus luminescens

Summary for 6EK4

• Entry DOI: 10.2210/pdb6ek4/pdb
• Descriptor: PaxB, SODIUM ION (3 entities in total)
• Functional Keywords: pathogens, pore forming toxins, alpha-helical, adventitious membrane protein, membrane protein
• Biological source: Photorhabdus luminescens
• Total number of polymer chains: 4
• Total formula weight: 162798.15

Authors

Braeuning, B.,Groll, M. (deposition date: 2017-09-25, release date: 2018-05-16, Last modification date: 2024-05-01)

Primary citation

Brauning, B.,Bertosin, E.,Praetorius, F.,Ihling, C.,Schatt, A.,Adler, A.,Richter, K.,Sinz, A.,Dietz, H.,Groll, M.
Structure and mechanism of the two-component alpha-helical pore-forming toxin YaxAB.
Nat Commun, 9:1806-1806, 2018

PubMed Abstract: Pore-forming toxins (PFT) are virulence factors that transform from soluble to membrane-bound states. The Yersinia YaxAB system represents a family of binary α-PFTs with orthologues in human, insect, and plant pathogens, with unknown structures. YaxAB was shown to be cytotoxic and likely involved in pathogenesis, though the molecular basis for its two-component lytic mechanism remains elusive. Here, we present crystal structures of YaxA and YaxB, together with a cryo-electron microscopy map of the YaxAB complex. Our structures reveal a pore predominantly composed of decamers of YaxA-YaxB heterodimers. Both subunits bear membrane-active moieties, but only YaxA is capable of binding to membranes by itself. YaxB can subsequently be recruited to membrane-associated YaxA and induced to present its lytic transmembrane helices. Pore formation can progress by further oligomerization of YaxA-YaxB dimers. Our results allow for a comparison between pore assemblies belonging to the wider ClyA-like family of α-PFTs, highlighting diverse pore architectures.

PubMed: 29728606
DOI: 10.1038/s41467-018-04139-2

Experimental method

X-RAY DIFFRACTION (2.8 Å)