Multifunctional Modification of Biologically Active Substances

Abstract

The article studies the interracting of oxidized cyclic cyclodextrin dextrans (CD) with the protein - bacterial streptokinase. The oxidation was carried out with potassium periodate; free aldehyde groups were formed in CD molecule during this process. Excess of potassium periodate was removed on a column using ion – exchange resin (anionite APA with acetate ion). Reaction between streptokinase and oxidized cyclic dextran was monitored by gel-permation chromatography (sephadex G-200). The mass of complex of streptokinase with exciding cyclodextrin goes up to 65 kDa (the ratio by moles is 1-3). One streptokinase macromolecule is bound to 14 molecules of CD. It was shown that the chemical reaction between streptokinase and cyclodextrin proceeded in a way which is similar to its reaction with oxidized linear dextrans. It was found that protein-bound CD retained the ability to absorb small molecules like adenosine in its inner shell. The complex of streptokinase with CD absorbs the molecule of adenosine and forms a new complex with adenosine intercalated in cyclodextrin part of the new complex.

Keywords

• cyclodextrin
• streptokinase
• adenosine
• chemical modification
• gelchromatography
• oxidation of oligosaccharides
• complex