par De Jonge, Natalie;Hohlweg, Walter;Garcia-Pino, Abel 
;Respondek, Michal;Buts, Lieven;Haesaerts, Sarah;Lah, Jurij;Zangger, Klaus;Loris, Remy
Référence The Journal of biological chemistry, 285, 8, page (5606-5613)
Publication Publié, 2010-02
;Respondek, Michal;Buts, Lieven;Haesaerts, Sarah;Lah, Jurij;Zangger, Klaus;Loris, RemyRéférence The Journal of biological chemistry, 285, 8, page (5606-5613)
Publication Publié, 2010-02
Article révisé par les pairs
| Résumé : | CcdB(Vfi) from Vibrio fischeri is a member of the CcdB family of toxins that poison covalent gyrase-DNA complexes. In solution CcdB(Vfi) is a dimer that unfolds to the corresponding monomeric components in a two-state fashion. In the unfolded state, the monomer retains a partial secondary structure. This observation correlates well with the crystal and NMR structures of the protein, which show a dimer with a hydrophobic core crossing the dimer interface. In contrast to its F plasmid homologue, CcdB(Vfi) possesses a rigid dimer interface, and the apparent relative rotations of the two subunits are due to structural plasticity of the monomer. CcdB(Vfi) shows a number of non-conservative substitutions compared with the F plasmid protein in both the CcdA and the gyrase binding sites. Although variation in the CcdA interaction site likely determines toxin-antitoxin specificity, substitutions in the gyrase-interacting region may have more profound functional implications. |
