Fast photoinduced electron transfer through DNA intercalation.

نویسندگان

  • C J Murphy
  • M R Arkin
  • N D Ghatlia
  • S Bossmann
  • N J Turro
  • J K Barton
چکیده

We report evidence for fast photoinduced electron transfer mediated by the DNA helix that requires metal complexes that are avid intercalators of DNA. Here the donor bis(phenanthroline)(dipyridophenazine)ruthenium(II) [Ru(phen)2dppz2+] and acceptor bis(9,10-phenanthrenequinone diimine)(phenanthroline)rhodium(III) [Rh(phi)2phen3+] intercalate into DNA with Kb > 10(6) M-1. Luminescence quenching experiments in the presence of two different lengths of DNA yield upward-curving Stern-Volmer plots and the loss of luminescence intensity far exceeds the change in emission lifetimes. In the presence of a nonintercalative electron acceptor, Ru(NH3)3+(6), Ru(phen)2dppz2+ luminescence is quenched much less efficiently compared to that found for the intercalative Rh(phi)2phen3+ quencher and follows linear Stern-Volmer kinetics; steady-state and time-resolved Stern-Volmer plots are comparable in scale. These experiments are consistent with a model involving fast long-range electron transfer between intercalators through the DNA helix.

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

DNA Intercalators and Using Them as Anticancer Drugs

Many anticancer drugs in clinical use interact with DNA through intercalation, which is process that starts with the transfer of the intercalating molecule from an aqueous environment to the hydrophobic space between two adjacent DNA base pairs. In general, intercalatig agents are two types: monofunctional and bifunctional. Monofunctional intercalators contain one intercalating unit and Bifunct...

متن کامل

DNA Intercalators and Using Them as Anticancer Drugs

Many anticancer drugs in clinical use interact with DNA through intercalation, which is process that starts with the transfer of the intercalating molecule from an aqueous environment to the hydrophobic space between two adjacent DNA base pairs. In general, intercalatig agents are two types: monofunctional and bifunctional. Monofunctional intercalators contain one intercalating unit and Bifunct...

متن کامل

Photoinduced electron transfer across molecular bridges: electron- and hole-transfer superexchange pathways.

Photoinduced electron transfer plays key roles in many areas of chemistry. Superexchange is an effective model to rationalize photoinduced electron transfer, particularly when molecular bridges between donor and acceptor subunits are present. In this tutorial review we discuss, within a superexchange framework, the complex role played by the bridge, with an emphasis on differences between therm...

متن کامل

Probing the B-to-Z-DNA duplex transition using terminally stacking ethynyl pyrene-modified adenosine and uridine bases.

Pyrene-modified adenosine and uridine bases located in the dangling positions of G,C-alternating oligodeoxynucleotides undergo pi-stacking in their B-DNA duplexes, but not in their Z-DNA duplexes; fluorescence quenching in the former, through photoinduced electron transfer, but not in the latter, allows the state of the B-to-Z-DNA transition to be characterized visually.

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

عنوان ژورنال:
  • Proceedings of the National Academy of Sciences of the United States of America

دوره 91 12  شماره 

صفحات  -

تاریخ انتشار 1994