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Guanine Can Direct Binding Specificity of Ru-dipyridophenazine (dppz) Complexes to DNA through Steric Effects.

ABSTRACT: X-ray crystal structures of three Λ-[Ru(L)₂ dppz]²⁺ complexes (dppz=dipyridophenazine; L=1,10-phenanthroline (phen), 2,2'-bipyridine (bpy)) bound to d((5BrC)GGC/GCCG) showed the compounds intercalated at a 5'-CG-3' step. The compounds bind through canted intercalation, with the binding angle determined by the guanine NH₂ group, in contrast to symmetrical intercalation previously observed at 5'-TA-3' sites. This result suggests that canted intercalation is preferred at 5'-CG-3' sites even though the site itself is symmetrical, and we hypothesise that symmetrical intercalation in a 5'-CG-3' step could give rise to a longer luminescence lifetime than canted intercalation.

SUBMITTER: Hall JP

PROVIDER: S-EPMC5412927 | biostudies-literature | 2017 Apr

REPOSITORIES: biostudies-literature

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Guanine Can Direct Binding Specificity of Ru-dipyridophenazine (dppz) Complexes to DNA through Steric Effects.

Hall James P JP Gurung Sarah P SP Henle Jessica J Poidl Patrick P Andersson Johanna J Lincoln Per P Winter Graeme G Sorensen Thomas T Cardin David J DJ Brazier John A JA Cardin Christine J CJ

Chemistry (Weinheim an der Bergstrasse, Germany) 20170206 21

X-ray crystal structures of three Λ-[Ru(L)2 dppz]2+ complexes (dppz=dipyridophenazine; L=1,10-phenanthroline (phen), 2,2'-bipyridine (bpy)) bound to d((5BrC)GGC/GCCG) showed the compounds intercalated at a 5'-CG-3' step. The compounds bind through canted intercalation, with the binding angle determined by the guanine NH2 group, in contrast to symmetrical intercalation previously observed at 5'-TA-3' sites. This result suggests that canted intercalation is preferr ...[more]

PMID: 28105682

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