Chemical Dissection of Protein Translocation through the Anthrax Toxin Pore


  • This research was supported by NIAID grants RO1-AI022021 and AI057159. The recombinant proteins employed here were prepared in the Biomolecule Production Core of the New England Regional Center of Excellence, supported by NIH grant number AI057159. We thank A. Fischer and A. Barker for helpful suggestions regarding cell cytotoxicity experiments and S. Walker and E. Doud for providing access to their ESI-QTOF MS.


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Through the pore: The N-terminal domain of the lethal factor of anthrax toxin was modified to probe protein translocation through the toxin pore. Replacing acidic residues with cysteic acid inhibited translocation, whereas introduction of D-amino acids or an alternating Lys–Glu sequence had no effect. The findings demonstrate independence of translocation from stereospecificity and strict sequence, and dependence on the charge state of acidic residues.