Figure 3
From: Putative DNA G-quadruplex formation within the promoters of Plasmodium falciparum var genes
Circular dichroism spectra of putative G-quadruplex sequences (PQS) from the upstream B regions of var genes in 150 mM potassium, sodium and ammonium cation. UpsB-Q-1 (blue), UpsB-Q-2 (red), UpsB-Q-3 (pink) and UpsB-Q-4 (green). Characteristic signatures of hybrid G-quadruplexes (i.e. containing a mixture of parallel and antiparallel strand orientations) are observed in potassium and ammonium. In sodium, G-quadruplexes are predominantly antiparallel.