DSSR-derived G-quadruplex features in PDB entry 5ls8
Poster "DSSR-Enabled Automatic Identification and Annotation of G-quadruplexes in the PDB" presented at the RNA2020 online meeting
Citation: before a paper dedicated to the DSSR-G4 module comes out, please cite the 2015 DSSR paper published in Nucleic Acids Research.
- X-ray (1.78 Å)
- Light-activated ruthenium complex bound to a DNA quadruplex
- McQuaid, K., Abell, H., Gurung, S.P., Allan, D.R., Winter, G., Sorensen, T., Cardin, D.J., Brazier, J.A., Cardin, C.J., Hall, J.P.: (2019) "Structural Studies Reveal Enantiospecific Recognition of a DNA G-Quadruplex by a Ruthenium Polypyridyl Complex." Angew.Chem.Int.Ed.Engl., 58, 9881-9885.
- By using X-ray crystallography, we show that the complexes Λ/Δ-[Ru(TAP)2 (11-CN-dppz)]2+ (TAP=1,4,5,8-tetraazaphenanthrene, dppz=dipyridophenazine) bind DNA G-quadruplex in an enantiospecific manner that parallels the specificity of these complexes with duplex DNA. The Λ complex crystallises with the normally parallel stranded d(TAGGGTTA) tetraplex to give the first such antiparallel strand assembly in which syn-guanosine is adjacent to the complex at the 5' end of the quadruplex core. SRCD measurements confirm that the same conformational switch occurs in solution. The Δ enantiomer, by contrast, is present in the structure but stacked at the ends of the assembly. In addition, we report the structure of Λ-[Ru(phen)2 (11-CN-dppz)]2+ bound to d(TCGGCGCCGA), a duplex-forming sequence, and use both structural models to provide insight into the motif-specific luminescence response of the isostructural phen analogue enantiomers.
- G4 notes
- 3 G-tetrads, 1 G4 helix, 1 G4 stem · (2+2), UDUD
1 glyco-bond=s-s- groove=wnwn planarity=0.456 type=bowl-2 nts=4 GGGG A.DG3,C.DG5,B.DG3,D.DG5 2 glyco-bond=-s-s groove=wnwn planarity=0.358 type=other nts=4 GGGG A.DG4,C.DG4,B.DG4,D.DG4 3 glyco-bond=-s-s groove=wnwn planarity=0.500 type=bowl-2 nts=4 GGGG A.DG5,C.DG3,B.DG5,D.DG3