Download MendeleySolution structure of a thrombin binding aptamer complex with a non-planar platinum(ii) compound.
Zhu, B.C., He, J., Xia, X.Y., Jiang, J., Liu, W., Liu, L.Y., Liang, B.B., Yao, H.G., Ke, Z., Xia, W., Mao, Z.W.(2022) Chem Sci 13: 8371-8379
- PubMed: 35919711
- DOI: https://doi.org/10.1039/d2sc01196d
- Primary Citation of Related Structures:
7V3T - PubMed Abstract:
Thrombin Binding Aptamer (TBA) is a monomolecular well-defined two G-tetrad antiparallel G-quadruplex DNA that inhibits the activity of human α-thrombin. In this report, we synthesized a quasi-cross-shaped platinum(ii) compound (L' 2 LPt) with one cyclometalated and two carbene ligands. We found L' 2 LPt has selective affinity to bind the TBA G-quadruplex. A fibrinogen clotting assay revealed that L' 2 LPt can abrogate the inhibitory activity of TBA against thrombin. We solved the 1 : 1 L' 2 LPt-TBA complex structure by NMR, which revealed a unique self-adaptive property of L' 2 LPt upon binding to TBA. In the complex, a carbene ligand of L' 2 LPt rotates to pair with the cyclometalated ligand to form a plane stacking over half of the TBA G-tetrad and covered by lateral TT loops. It is notable that the heavy atom Pt stays out of the G-tetrad. Meanwhile, the other carbene ligand remains relatively perpendicular and forms a hydrogen bond with a guanine to anchor the L' 2 LPt position. This structure exhibits a quasi-cross-shaped Pt(ii) compound bound to the G-quadruplex with an unusual "wall-mounted" binding mode. Our structures provide insights into the specific recognition of antiparallel G-quadruplex DNA by a self-adaptive Pt(ii) compound and useful information for the design of selective G-quadruplex targeting non-planar molecules.
Organizational Affiliation:
MOE Key Laboratory of Bioinorganic and Synthetic Chemistry, School of Chemistry, Sun Yat-sen University Guangzhou 510275 China cesmzw@mail.sysu.edu.cn liuwenting@mail.sysu.edu.cn xiawei5@mail.sysu.edu.cn.
