Sci Rep. 2015 Sep 25;5:14352. doi: 10.1038/srep14352.

Crystal structure of Streptococcus pneumoniae pneumolysin provides key insights into early steps of pore formation.

Lawrence SL1, Feil SC1, Morton CJ1, Farrand AJ2, Mulhern TD3, Gorman MA1, Wade KR2, Tweten RK2, Parker MW1,3.

Author information

 

 

Abstract

Pore-forming proteins are weapons often used by bacterial pathogens to breach the membrane barrier of target cells. Despite their critical role in infection important structural aspects of the mechanism of how these proteins assemble into pores remain unknown. Streptococcus pneumoniae is the world's leading cause of pneumonia, meningitis, bacteremia and otitis media. Pneumolysin (PLY) is a major virulence factor of S. pneumoniae and a target for both small molecule drug development and vaccines. PLY is a member of the cholesterol-dependent cytolysins (CDCs), a family of pore-forming toxins that form gigantic pores in cell membranes. Here we present the structure of PLY determined by X-ray crystallography and, in solution, by small-angle X-ray scattering. The crystal structure reveals PLY assembles as a linear oligomer that provides key structural insights into the poorly understood early monomer-monomer interactions of CDCs at the membrane surface.

PMID: 26403197 [PubMed - in process] PMCID: PMC4585913