| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 1429577 | Materials Science and Engineering: C | 2012 | 10 Pages |
Herein, we demonstrate the physical and chemical characterizations of the supramolecular complex formed between β-cyclodextrin (βCD) and bradykinin potentiating nonapeptide (BPP9a), an endogenous toxin found in Bothrops jararaca. Circular dichroism results indicate a conformational change in the BPP9a secondary structure upon its complexation with βCD. Nuclear magnetic resonance results, mainly from NOESY experiments, and theoretical calculations showed a favorable interaction between the tryptophan residue of BPP9a and the βCD cavity. Thermodynamic inclusion parameters were investigated by isothermal titration calorimetry, demonstrating that βCD/BPP9a complex formation is an exothermic process that results in a reduction in entropy. Additionally, in vitro degradation study of BPP9a against trypsin (37 °C, pH 7.2) showed higher stability of peptide in presence of βCD. This βCD/BPP9a complex, which presents new chemical properties arising from the peptide inclusion process, may be useful as an antihypertensive drug in oral pharmaceutical formulations.
Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slideHighlights► Cd and NMR showed evidences for the existence of more than one structure in solution. ► Complexation with βCD reduces the conformational rigidity of the peptide. ► βCD cavity recognize Trp and/or Pro segments of BPP9a. ► Interactions involving disaggregation of BPP9a assemblies and binding with βCD.
