Structure of Staphylococcal α-Hemolysin, a Heptameric Transmembrane Pore

@article{Song1996StructureOS,
  title={Structure of Staphylococcal $\alpha$-Hemolysin, a Heptameric Transmembrane Pore},
  author={Langzhou Song and Michael R. Hobaugh and C. Shustak and Stephen Cheley and Hagan Bayley and J. Eric Gouaux},
  journal={Science},
  year={1996},
  volume={274},
  pages={1859 - 1865}
}
The structure of the Staphylococcus aureus α-hemolysin pore has been determined to 1.9 Å resolution. Contained within the mushroom-shaped homo-oligomeric heptamer is a solvent-filled channel, 100 Å in length, that runs along the sevenfold axis and ranges from 14 Å to 46 Å in diameter. The lytic, transmembrane domain comprises the lower half of a 14-strand antiparallel β barrel, to which each protomer contributes two β strands, each 65 Å long. The interior of the β barrel is primarily… 

α-Hemolysin fromStaphylococcus aureus:An Archetype of β-Barrel, Channel-Forming Toxins

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Crystal structure of the octameric pore of staphylococcal γ-hemolysin reveals the β-barrel pore formation mechanism by two components

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Molecular basis of transmembrane beta-barrel formation of staphylococcal pore-forming toxins.

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Preliminary X-ray crystallographic study of staphylococcal α-haemolysin monomer.

  • T. SugawaraD. Yamashita M. Yao
  • Chemistry
    Acta crystallographica. Section F, Structural biology and crystallization communications
  • 2013
The relative orientation among molecules was distinct from that of the pore, indicating that the crystal contained monomeric α-haemolysin, which is a β-barrel pore-forming toxin expressed by Staphylococcus aureus.

Crystal structure of Staphylococcal LukF delineates conformational changes accompanying formation of a transmembrane channel

The LukF structure illustrates how a channel–forming toxin masks protein–protein and protein–membrane interfaces prior to cell binding and assembly, and together with the α–hemolysin heptamer structure, they define the end points on the pathway of toxin assembly.

Structure-Function Relationships of a Novel Bacterial Toxin, Hemolysin E

Gel filtration analyses suggested that immobilizing αG inhibits HlyE activity at a late stage of pore formation, whereas in solution it prevents aggregation and consequent inactivation.

Distinction between Pore Assembly by Staphylococcal α-Toxin versus Leukotoxins

Modifications of bipartite leukotoxins by two different processes, using fusion with glutathione S-transferase and bridging of the N-terminal extremity to the adjacent β-sheet via disulphide bridges, are not deleterious for biological activity and illustrate a microheterogeneity of the structural organizations between bipartites and α-toxin.

Subunit Dimers of α-Hemolysin Expand the Engineering Toolbox for Protein Nanopores*

The ability to incorporate subunit dimers into αHL pores increases the range of structures that can be obtained from engineered protein nanopores, and changes the stoichiometry of the central pore of αHL by the concatenation of subunits.
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It is reported that analysis of x-ray diffraction data and chemical modification experiments indicate that the alpha HL oligomer is a heptamer, and data establish the hePTameric oligomerization state of thealpha HL transmembrane pore both in three-dimensional crystals and on a biological membrane.

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Key Residues for Membrane Binding, Oligomerization, and Pore Forming Activity of Staphylococcal α-Hemolysin Identified by Cysteine Scanning Mutagenesis and Targeted Chemical Modification (*)

Through detailed examination of the phenotypes of the mutant and modified hemolysins, this study has pinpointed residues and regions in the αHL polypeptide chain that are important for binding to rRBC, oligomer formation and pore activity.

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