Structure determination of the Pb$^{2+}$-specific GT aptamer using SAXS and molecular modeling methods

Aptamer GT conjugated with gold nanoparticles is specific for heavy metal ions and can be used for water quality control and environmental monitoring. Circular dichroism (CD) and small-angle X-ray scattering (SAXS) measurements were performed to determine the structure of the aptamer complex with lead (II) ions. Comparison of the measurement results with different options of the spatial structure of the complexes obtained using molecular modeling allowed us to determine how the aptamer changes its conformation due to interacting with the target.