Electron transfer through DNA

B. Giese, S. Wessely, M Spormann, U. Lindemann, E. Meggers, M. E. Michel-Beyerle, On the Mechanism of Long-Range Electron Transfer through DNA , Angew. Chem, Int. Ed. 1999,38, 996-998. 

Kelley SO, Jackson NM, Hill MG, Barton JK (1999) Long-range electron transfer through DNA films. Angew Chem Int Ed 38 941-945... 

Giese B., Long-distance electron transfer through DNA, Annu. Rev. Biochem., 2002,71,51-70. 

INTERFACIAL ELECTROCHEMICAL ELECTRON TRANSFER THROUGH DNA-BASED MOLECULES... 

Ye, Y., Jiang, Y. (2000). Electronic structures and long-range electron transfer through DNA molecules. Int J Quant Chem 78, 112-130. 

Ferrocenylated ODNs were first immobilized in a self-assembled redox-active monolayer on Au electrodes by Letsinger and co-workers.Upon hybridization of a complementary strand, the electrochemical potential of the ferrocene changes. In addition to applications as electrochemical DNA sensors, such self-assembled DNA monolayers with electro-active groups may provide information on the mechanism of electron transfer through DNA, and indirectly also on molecular mobility within short stretches of DNA. " We have recently extended this idea by the use of immobilized metallocene-labeled PNA on Au electrodes. Because PNA is an uncharged molecule, a surface with improved properties forms, and electrochemical detection, also of single mismatches, is facilitated. 

Giese B, Wessely S, Spormann M, Lindemann U, Megjers E, Michel-Beyerle ME. On the mechanism of long-range electron transfer through DNA. Angetv Chem Int Ed. 1999 38 996-998. 

Meggers E, Kusch D, Spichty M, WiUe U, Giese B. Electron transfer through DNA in the course of radical-induced strand cleavage. Angew Chem Int Ed. 1998 37 460-462. 

Figure 7.14. Schematic diagram of SECM measurement of electron transfer through DNA dupiexes that aiiowed to provided a possible mechanism for the differences in charger transfer resistances before and after Zn + addition to dsDNA films. B. Liu, A. J. Bard, C.-Z. Li and H.-B. Kraatz ]. Phys. Chem. B 2005,109, 5193-5198. Cop50 ight 2005 American Chemical Society.

To explore the utility of DNA-mediated electron-transfer events for biosensing applications, an electrochemical assay was developed [23-25]. Electrochemical sensors are typically more portable and inexpensive than those using fluorescence-based detection, hence a system suitable for monitoring electron transfer through DNA duplexes immobilized on the surface of an electrode was sought. 

C. Long-Range Electron Transfer Through DNA Films... 

Figure 5 Series of DM-modifled duplexes constructed to evaluate long-range electron transfer through DNA films. (Adapted from Ref. 24.)...

The electron affinities of the DNA bases are fundamentally important to the understanding of electron transfer through DNA as well as the localization of excess electrons on DNA [50]. As a consequence the electron affinities (EA) of the DNA bases have been under active investigation in our laboratory [16, 34, 47, 51, 52],... 

Various base analogues have been examined in electron transfer through DNA, in particular a comparison of electron acceptors 5-bromo-dU and a thymine dimer, where it was observed that the rate of cleavage of the thymine dimer is about one order of magnitude slower than observed for 5-bromo-dU." The presence of an abasic site adjacent to guanine runs influences the rate of electron transport where efficiency is higher if the abasic site is 3 -to the guanine residues. " Various photo-oxidants have... 

---