Aptamer-peptide conjugates as a new strategy to modulate human α-thrombin binding affinity

Area of Science:

• Biochemistry
• Biotechnology
• Molecular Biology

Background:

• Aptamers are nucleic acid molecules that bind targets with high specificity, valuable for biosensor development.
• Alpha-thrombin plays a key role in hemostasis and thrombosis; its abnormal activity is linked to various diseases.
• Accurate thrombin detection is crucial for early disease diagnosis and treatment.

Purpose of the Study:

• To modulate the interaction between alpha-thrombin and the aptamer TBA15.
• To develop a novel approach for enhancing thrombin detection using aptamer-peptide conjugates.
• To investigate the potential of these conjugates for blocking thrombin activity.

Main Methods:

• Chemical conjugation of TBA15 aptamer with peptide sequences derived from human factor V.
• Surface Plasmon Resonance (SPR) for analyzing binding kinetics and sensitivity.
• Electrophoresis Mobility Shift Assay (EMSA) to confirm aptamer-target interactions.
• Molecular Dynamics (MD) simulations to elucidate interaction mechanisms.

Main Results:

• Conjugation of TBA15 with TBA-G3EIF-Ac peptide significantly enhanced analytical performance for thrombin detection.
• Achieved a limit of detection as low as 44.9 pM for thrombin using the modified aptamer.
• SPR and EMSA results corroborated the enhanced binding and detection capabilities.
• MD simulations provided insights into the molecular interactions between thrombin and the TBA-peptide conjugates.

Conclusions:

• The combination of TBA15 aptamer with specific interacting peptides offers a promising strategy for sensitive thrombin detection devices.
• Modified aptamers demonstrate potential for early diagnosis of thrombin-related diseases.
• These aptamer-peptide conjugates show potential as therapeutic candidates to inhibit thrombin activity.