DSSR-PyMOL cartoon-block schematics: PDB entry 6fq2

PDB-id

6fq2; DSSR-derived features in text and JSON formats

Class

DNA

Method

X-ray (2.31 Å)

Summary

Structure of minimal sequence for left -handed g-quadruplex formation

Reference

Bakalar B, Heddi B, Schmitt E, Mechulam Y, Phan AT (2019): "A Minimal Sequence for Left-Handed G-Quadruplex Formation." Angew. Chem. Int. Ed. Engl., 58, 2331-2335. doi: 10.1002/anie.201812628.

Abstract

Recently, we observed the first example of a left-handed G-quadruplex structure formed by natural DNA, named Z-G4. We analysed the Z-G4 structure and inspected its primary 28-nt sequence in order to identify motifs that convey the unique left-handed twist. Using CD, NMR spectroscopy and X-ray crystallography, we revealed a minimal sequence motif of 12 nt GTGGTGGTGGTG for the left-handed DNA G-quadruplex formation, which is found to be highly abundant in the human genome. A systematic analysis of thymine loop mutations revealed a moderate sequence tolerance, which would further broaden the space of sequences prone to left-handed G-quadruplex formation.