Format

Send to

Choose Destination
Cell. 1999 May 28;97(5):647-55.

Two structural transitions in membrane pore formation by pneumolysin, the pore-forming toxin of Streptococcus pneumoniae.

Author information

1
Department of Biochemistry, University of Leicester, United Kingdom.

Abstract

The human pathogen Streptococcus pneumoniae produces soluble pneumolysin monomers that bind host cell membranes to form ring-shaped, oligomeric pores. We have determined three-dimensional structures of a helical oligomer of pneumolysin and of a membrane-bound ring form by cryo-electron microscopy. Fitting the four domains from the crystal structure of the closely related perfringolysin reveals major domain rotations during pore assembly. Oligomerization results in the expulsion of domain 3 from its original position in the monomer. However, domain 3 reassociates with the other domains in the membrane pore form. The base of domain 4 contacts the bilayer, possibly along with an extension of domain 3. These results reveal a two-stage mechanism for pore formation by the cholesterol-binding toxins.

PMID:
10367893
DOI:
10.1016/s0092-8674(00)80775-8
[Indexed for MEDLINE]
Free full text

Supplemental Content

Full text links

Icon for Elsevier Science
Loading ...
Support Center