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The Importance of Correct Protein Concentration for Kinetics and Affinity Determination in Structure-function Analysis
Published on: March 17, 2010
A supramolecular complex between proteinases and beta-cyclodextrin that preserves enzymatic activity: physicochemical
Angelo M L Denadai1, Marcelo M Santoro, Miriam T P Lopes
1Department of Chemistry, Institute of Exact Sciences, Universidade Federal de Minas Gerais (UFMG), Antonio Carlos 6627, Belo Horizonte 31270-901, Brazil.
Summary
Beta-cyclodextrin (betaCD) forms supramolecular complexes with plant cysteine proteinases, enhancing their therapeutic potential. These complexes exhibit sustained proteolytic activity after initial dissolution, indicating their suitability for drug delivery.
Area of Science:
- Supramolecular Chemistry
- Biochemistry
- Materials Science
Background:
- Cyclodextrins (CDs) are versatile drug delivery systems due to their ability to form inclusion complexes.
- Plant cysteine proteinases from Caricaceae and Bromeliaceae possess therapeutic properties, including anti-inflammatory and wound-healing effects.
Purpose of the Study:
- To investigate the complexation between beta-cyclodextrin (betaCD) and a fraction (P1G10) of bioactive proteinases from Carica candamarcensis.
- To characterize the physicochemical properties of the resulting solid-state self-assembled complexes.
Main Methods:
- Solid-state characterization using FTIR, TG, DSC, XRD, and NMR.
- Solution studies employing CD, ITC, and amidase activity assays.
- Analysis of interactions at varying P1G10:betaCD mass ratios.
Main Results:
- Evidence of complex formation between P1G10 and betaCD, driven by hydrophobic interactions, hydrogen bonding, and van der Waals forces.
- Microcalorimetry indicated a favorable enthalpic contribution to complexation.
- The amidase activity of the complex showed a delayed onset but sustained proteolytic action for up to 16 days post-dissolution.
Conclusions:
- Beta-cyclodextrins are promising candidates for complexing cysteine proteinases.
- The resulting supramolecular arrays demonstrate sustained proteolytic activity, highlighting potential for advanced drug delivery applications.
- The study provides insights into the non-covalent interactions governing these complexes.
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