Calcium-Induced Folding and Stabilization of the Intrinsically Disordered RTX Domain of the CyaA Toxin
| Autor: | Anna Wozniak, Ana Cristina Sotomayor Pérez, Bruno Baron, Johanna C. Karst, Patrick England, Daniel Ladant, Alexandre Chenal |
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| Přispěvatelé: | Biochimie des Interactions Macromoléculaires / Biochemistry of Macromolecular Interactions, Institut Pasteur [Paris] (IP)-Centre National de la Recherche Scientifique (CNRS), Biophysique Moléculaire (Plate-forme), A.C., J.K., and A.K.W. were supported by the Theravac program (6thFramework Project FP6-LIFESCIHEALTH of the European Community, Reference: LSHB-CT-2003-503582). A.C.S.P. was supported by the Allocation de These de la Region Ile-de-France (PhD program). The project was supported by the Centre National de la Recherche Scientifique, Institut Pasteur, and the Agence Nationale de la Recherche, programme Jeunes Chercheurs., ANR-09-JCJC-0012,TransloXyaA(2009), Institut Pasteur [Paris]-Centre National de la Recherche Scientifique (CNRS) |
| Rok vydání: | 2010 |
| Předmět: |
Models
Molecular Protein Folding Bordetella pertussis Circular dichroism Sodium Chloride MESH: Circular Dichroism MESH: Bordetella pertussis MESH: Protein Structure Tertiary chemistry.chemical_compound Spectroscopy Fourier Transform Infrared Urea Guanidine 0303 health sciences biology Protein Stability Circular Dichroism 030302 biochemistry & molecular biology Tryptophan Folding (chemistry) Biochemistry MESH: Calcium Adenylate Cyclase Toxin Protein folding MESH: Models Molecular MESH: Sodium Chloride MESH: Protein Folding Biophysics chemistry.chemical_element Calcium chemistry Fluorescence Calcium/pharmacology MESH: Spectroscopy Fourier Transform Infrared 03 medical and health sciences MESH: Protein Stability [SDV.BBM]Life Sciences [q-bio]/Biochemistry Molecular Biology MESH: Guanidine MESH: Tryptophan MESH: Urea 030304 developmental biology Protein MESH: Fluorescence cyaA MESH: Adenylate Cyclase Toxin biology.organism_classification Protein Structure Tertiary metabolism |
| Zdroj: | Biophysical Journal Biophysical Journal, 2010, 99 (11), pp.3744-53. ⟨10.1016/j.bpj.2010.10.016⟩ Biophysical Journal, Biophysical Society, 2010, 99 (11), pp.3744-53. ⟨10.1016/j.bpj.2010.10.016⟩ |
| ISSN: | 0006-3495 1542-0086 |
| Popis: | International audience; The adenylate cyclase toxin (CyaA) is one of the major virulence factors of Bordetella pertussis, the causative agent of whooping cough. Its C-terminal region, the receptor-binding domain (RD), contains ∼40 calcium-binding Repeat in ToXin (RTX) motifs, which are characteristic of many virulence factors of pathogenic bacteria. We previously showed that RD is intrinsically disordered in the absence of calcium and acquires its functional three-dimensional structure upon calcium binding. To gain further insight into the physicochemical properties of RD, we characterized its calcium-induced conformational and stability changes by combining spectroscopic approaches. We show that RD, in the absence of calcium, adopts premolten globule conformations, due in part to the strong internal electrostatic repulsions between the negative charges of the aspartate-rich polypeptide sequence. Accordingly, sodium is able to screen these electrostatic repulsions, allowing a partial compaction of the polypeptide, whereas calcium triggers a strong compaction as well as the acquisition of secondary and tertiary structures in a highly cooperative manner. The differential sensitivity of the calcium-loaded state to guanidinium- and urea-induced denaturations provides further evidence that electrostatic interactions play a critical role in the folding and stability of RD. These results provide new insights into the folding/function relationship of the RTX motifs. |
| Databáze: | OpenAIRE |
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