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Sialyllactose-binding modified DNA aptamer bearing additional functionality by SELEX.

Mohammad Mehedi Masud·Masayasu Kuwahara·Hiroaki Ozaki·Hiroaki Sawai
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Abstract

We produced a novel cationic-charged modified DNA aptamer for sialyllactose that is a ubiquitous component of the cell surface responsible for the infection of several viruses by using the magnetic-particle-based SELEX method. After 13 rounds of selection we selected 22 clones as sialyllactose-binding DNA aptamers composed of several modified thymidines. The DNA aptamers could form a three-way junction structure that likely forms a binding site for siallyllactose. The three-way junction structure contains several modified thymidines bearing a positively-charged amino group at the C5 position, which could enhance the binding ability for silalyllactose which has a negatively-charged carboxyl group. The dissociation constant of the aptamer that showed the strongest sialyllactose-binding ability among the clones of the aptamers was 4.9 microM.

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Binding SitesDNAGene LibraryLactoseMembrane GlycoproteinsModels, MolecularNucleic Acid ConformationThymidineJournal ArticleResearch Support, Non-U.S. Gov't

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Mohammad Mehedi Masud, Masayasu Kuwahara, Hiroaki Ozaki, Hiroaki Sawai. 2004-03-01. Sialyllactose-binding modified DNA aptamer bearing additional functionality by SELEX.. https://doi.org/10.1016/j.bmc.2003.12.009

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