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Evaluation of the Interplay Between the Complement Protein C1q and Hyaluronic Acid in Promoting Cell Adhesion
Published on: June 15, 2019
Binding of bivalent cations by hyaluronate in aqueous solution
Guido Furth1, Robert Knierim, Volker Buss
1Fachbereich Chemie, Universität Duisburg-Essen, 45 117 Essen, Germany.
International Journal of Biological Macromolecules
|October 16, 2007
Summary
Sodium hyaluronate binds various bivalent cations, including heavy metals, with one cation per five disaccharide units. This interaction involves the acetamide group, forming a complex structure.
Area of Science:
- Biochemistry
- Polymer Science
- Biophysical Chemistry
Background:
- Sodium hyaluronate is a crucial glycosaminoglycan with diverse biological roles.
- Understanding its interaction with metal ions is vital for applications in medicine and biomaterials.
- Dextran serves as a control, showing no specific cation interactions.
Purpose of the Study:
- To investigate the binding mechanisms between sodium hyaluronate and various bivalent cations.
- To determine the stoichiometry and structural aspects of the resulting complexes.
- To compare cation binding affinity and specificity.
Main Methods:
- Conductometry
- Viscosimetry
- Circular dichroism spectroscopy
- Nuclear magnetic resonance (NMR) spectroscopy
Main Results:
- Sodium hyaluronate binds diverse bivalent cations (Ca2+, Mg2+, Mn2+, Fe2+, Cu2+, Zn2+, Cd2+, Pb2+) at pH 6.
- A molar ratio of approximately one bivalent cation to five disaccharide units was determined.
- Heavy metal ions (Cd2+, Pb2+) exhibit stronger binding than lighter cations (Ca2+, Mg2+).
- Spectroscopic data indicate involvement of the acetamide group in cation complexation.
Conclusions:
- Sodium hyaluronate forms specific complexes with bivalent cations.
- The binding involves electrostatic interactions and the acetamide group of the hyaluronate chain.
- A proposed binding structure involves two disaccharide units per cation.
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