Charge transfer in DNA

Long-Range Charge Transfer in DNA I Volume Editor Schuster, G.B. 

Wagenknecht HA (2008) Charge transfer in DNA from mechanism to application. Wiley-VCH, Weinheim, New York... 

Rosch N, Voityuk AA (2004) Quantum Chemical Calculation of Donor-Acceptor Coupling for Charge Transfer in DNA. 237 37-72 Rohovec J, see Frullano L (2002) 221 25-60... 

Charge transfer in DNA occurs under two distinctly different conditions one which is temperature-independent and the other which is not. The mechanism underpinning the former is tunneling, while the latter is controlled by an activation barrier that must be hopped over. Of these two, tunneling is the one better characterized. 

Tunneling as a mechanism of charge transfer in DNA has received widespread attention (see, for example. Refs. 117 and 132). Recently, definitive proof that tunneling in DNA occurs has been reported by Sevilla et al. [118-121,133]. Key to this proof is the demonstration that the observed rates of hole and electron transfer are independent of temperature from 4 to 130 K. We summarize their findings here. 

Charge transfer in DNA is summarized by the scheme shown in Fig. 3. Holes on the sugar-phosphate (SP) tunnel to the nearest base at a rate k in competition with the deprotonation rate, forming sugar products (spr ). Holes on the bases (B ) tunnel between... 

Fig. 3 Charge transfer in DNA hairpins after photoexcitation of stilbene linker (St) by a laser pulse [45]. A hole, first, undergoes a transition from photoexcited St to the adjacent GC pair as shown by the solid arrow. Then it can either hop to next GC pairs (dot-dashed arrow) or return to St with the subsequent electron-hole recombination (dotted arrow)...

Electrical conduction in DNA has become a highly contentious subfield of its own. The uncertainties here are even greater than those in the chemical measurements of charge transfer in DNA, partly because of the greater strand length generally involved, and partly because of the necessity for making contacts in measurement of DC conduction. 

Quantum Chemical Calculation of Donor-Acceptor Coupling for Charge Transfer in DNA... 

The majority of experiments on charge transfer in DNA deal with hole transfer. There are only few experimental studies pertaining to the transfer of excess electrons in DNA [89-91]. Theoretical studies focused on electron affinities of bases and their complexes [92-95]. 

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