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Updated: Jul 3, 2026
06:02
Determining the Thermodynamic and Kinetic Association of a DNA Aptamer and Tetracycline Using Isothermal Titration Calorimetry
Published on: August 23, 2022
Single-stranded DNA aptamers specific for antibiotics tetracyclines.
Javed H Niazi1, Su Jin Lee, Man Bock Gu
1College of Life Sciences and Biotechnology, Korea University, Anam-dong, Seongbuk-Gu, Seoul 136-701, Republic of Korea.
Bioorganic & Medicinal Chemistry
|July 12, 2008
Summary
Researchers identified tetracycline group specific (TGS) ssDNA aptamers using a modified SELEX method. These aptamers show high affinity for the tetracycline backbone and have potential applications in drug delivery and detection.
Area of Science:
- Biochemistry
- Molecular Biology
- Drug Discovery
Background:
- Tetracyclines (TCs) are a class of antibiotics with a common tetracycline (TET) nucleus.
- Variations at the X(1) and X(2) positions define different TCs like oxytetracycline (OTC) and doxycycline (DOX).
Purpose of the Study:
- To identify tetracycline group specific (TGS) ssDNA aptamers.
- To characterize the affinity and specificity of these aptamers to the tetracycline backbone and its analogues.
Main Methods:
- Modified SELEX (Systematic Evolution of Ligands by Exponential Enrichment) method was employed.
- Tosyl-activated magnetic beads (TMB) coated with OTC, TET, and DOX were used as targets and counter-targets.
- Counter-selection steps were used to eliminate aptamers binding to only one specific TC.
Main Results:
- Twenty TGS-aptamers were selected, with seven (T7, T15, T19, T20, T22, T23, T24) showing high affinity to the TET backbone (K(d)=63-483 nM).
- Aptamer specificity generally followed the SELEX process order (OTC>TET>DOX), with T22 showing higher specificity for TET.
- Consensus sequence motifs, including GGTGTGG and TGTGCT, were identified and predicted to be crucial for affinity and specificity.
Conclusions:
- Novel TGS ssDNA aptamers with high affinity and specificity for the tetracycline backbone were successfully identified.
- These aptamers possess potential applications in targeted drug delivery and the detection of TCs in pharmaceuticals and food products.
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