Ozgül Persil Çetinkol

Publications (2)11.97 Total impact

• Source

  Available from: PubMed Central

  Article: Molecular dynamics simulations and coupled nucleotide substitution experiments indicate the nature of A{middle dot}A base pairing and a putative structure of the coralyne-induced homo-adenine duplex.

  In Suk Joung, Ozgül Persil Cetinkol, Nicholas V Hud, Thomas E Cheatham
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  ABSTRACT: Coralyne is an alkaloid drug that binds homo-adenine DNA (and RNA) oligonucleotides more tightly than it does Watson-Crick DNA. Hud's laboratory has shown that poly(dA) in the presence of coralyne forms an anti-parallel duplex, however attempts to determine the structure by NMR spectroscopy and X-ray crystallography have been unsuccessful. Assuming adenine-adenine hydrogen bonding between the two poly(dA) strands, we constructed 40 hypothetical homo-(dA) anti-parallel duplexes and docked coralyne into the six most favorable duplex structures. The two most stable structures had trans glycosidic bonds, but distinct pairing geometries, i.e. either Watson-Crick Hoogsteen (transWH) or Watson-Crick Watson-Crick (transWW) with stability of transWH > transWW. To narrow down the possibilities, 7-deaza adenine base substitutions (dA-->7) were engineered into homo-(dA) sequences. These substitutions significantly reduced the thermal stability of the coralyne-induced homo-(dA) structure. These experiments strongly suggest the involvement of N7 in the coralyne-induced A.A base pairs. Moreover, due to the differential effect on melting as a function of the location of the dA-->7 mutations, these results are consistent with the N1-N7 base pairing of the transWH pairs. Together, the simulation and base substitution experiments predict that the coralyne-induced homo-(dA) duplex structure adopts the transWH geometry.
  Nucleic Acids Research 10/2009; 37(22):7715-27. · 8.03 Impact Factor
• Article: Submicromolar, selective G-quadruplex ligands from one pot: thermodynamic and structural studies of human telomeric DNA binding by azacyanines.

  Ozgül Persil Cetinkol, Aaron E Engelhart, Rupesh K Nanjunda, W David Wilson, Nicholas V Hud
  ChemBioChem 08/2008; 9(12):1889-92. · 3.94 Impact Factor