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Structure of the NheA component of the Nhe toxin from Bacillus cereus: implications for function.

ABSTRACT: The structure of NheA, a component of the Bacillus cereus Nhe tripartite toxin, has been solved at 2.05 Å resolution using selenomethionine multiple-wavelength anomalous dispersion (MAD). The structure shows it to have a fold that is similar to the Bacillus cereus Hbl-B and E. coli ClyA toxins, and it is therefore a member of the ClyA superfamily of ?-helical pore forming toxins (?-PFTs), although its head domain is significantly enlarged compared with those of ClyA or Hbl-B. The hydrophobic ?-hairpin structure that is a characteristic of these toxins is replaced by an amphipathic ?-hairpin connected to the main structure via a ?-latch that is reminiscent of a similar structure in the ?-PFT Staphylococcus aureus ?-hemolysin. Taken together these results suggest that, although it is a member of an archetypal ?-PFT family of toxins, NheA may be capable of forming a ? rather than an ? pore.

SUBMITTER: Ganash M

PROVIDER: S-EPMC3769298 | biostudies-literature | 2013

REPOSITORIES: biostudies-literature

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Structure of the NheA component of the Nhe toxin from Bacillus cereus: implications for function.

Ganash Magdah M Phung Danh D Sedelnikova Svetlana E SE Lindbäck Toril T Granum Per Einar PE Artymiuk Peter J PJ

PloS one 20130910 9

The structure of NheA, a component of the Bacillus cereus Nhe tripartite toxin, has been solved at 2.05 Å resolution using selenomethionine multiple-wavelength anomalous dispersion (MAD). The structure shows it to have a fold that is similar to the Bacillus cereus Hbl-B and E. coli ClyA toxins, and it is therefore a member of the ClyA superfamily of α-helical pore forming toxins (α-PFTs), although its head domain is significantly enlarged compared with those of ClyA or Hbl-B. The hydrophobic β-h ...[more]

PMID: 24040335

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