Pore-forming properties of the major 53-kilodalton surface antigen from the outer sheath of Treponema denticola

Infect Immun. 1993 May;61(5):1694-9. doi: 10.1128/iai.61.5.1694-1699.1993.


A 53-kDa protein from the outer sheath of the oral spirochete Treponema denticola was purified to homogeneity and shown to reconstitute channels in black lipid bilayer model membranes. The channel had a single-channel conductance of 1.8 nS in 0.1 M KCl, making this the largest porin channel observed to date (estimated diameter, 3.4 nm). Electron micrographs of 53-kDa-protein-containing outer sheaths of T. denticola showed a regular hexagonal array of darker staining pits.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Antigens, Bacterial / chemistry*
  • Antigens, Surface / chemistry*
  • Bacterial Adhesion
  • Bacterial Outer Membrane Proteins / chemistry*
  • Electric Conductivity
  • Ion Channel Gating
  • Ion Channels / chemistry*
  • Membranes, Artificial
  • Microscopy, Electron
  • Molecular Weight
  • Porins
  • Treponema / chemistry*
  • Treponema / ultrastructure


  • Antigens, Bacterial
  • Antigens, Surface
  • Bacterial Outer Membrane Proteins
  • Ion Channels
  • Membranes, Artificial
  • Porins