Cys−Cys Cross-Linking Shows Contact between the N-Terminus of Lethal Factor and Phe427 of the Anthrax Toxin Pore
نویسندگان
چکیده
Electrophysiological studies of wild-type and mutated forms of anthrax protective antigen (PA) suggest that the Phe clamp, a structure formed by the Phe427 residues within the lumen of the oligomeric PA pore, binds the unstructured N-terminus of the lethal factor and the edema factor during initiation of translocation. We now show by electrophysiological measurements and gel shift assays that a single Cys introduced into the Phe clamp can form a disulfide bond with a Cys placed at the N-terminus of the isolated N-terminal domain of LF. These results demonstrate direct contact of these Cys residues, supporting a model in which the interaction of the unstructured N-terminus of the translocated moieties with the Phe clamp initiates N- to C-terminal threading of these moieties through the pore.
منابع مشابه
A model of anthrax toxin lethal factor bound to protective antigen.
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عنوان ژورنال:
دوره 50 شماره
صفحات -
تاریخ انتشار 2011