Electron transfer characteristics of 2′-deoxy-2′-fluoro-arabinonucleic acid, a nucleic acid with enhanced chemical stability

Abstract

The non-biological nucleic acid 2'-deoxy-2'-fluoro-arabinonucleic acid (2'F-ANA) may be of use because of its higher chemical stability than DNA in terms of resistance to hydrolysis and nuclease degradation. In order to investigate the charge transfer characteristics of 2'F-ANA, of relevance to applications in nucleic acid-based biosensors and chip technologies, we compare the electronic couplings for hole transfer between stacked nucleobase pairs in DNA and 2'F-ANA by carrying out density functional theory (DFT) calculations on geometries taken from molecular dynamics simulations. We find similar averages and distribution widths of the base-pair couplings in the two systems. On the basis of this result, 2'F-ANA is expected to have charge transfer properties similar to those of DNA, while offering the advantage of enhanced chemical stability. As such, 2'F-ANA may serve as a possible alternative to DNA for use in a broad range of nanobiotechnological applications. Furthermore, we show that the (experimentally observed) enhanced chemical stability resulting from the backbone modifications does not cause reduced fluctuations of the base-pair electronic couplings around the values found for "ideal" B-DNA (with standard step parameter values). Our study also supports the use of a DFT implementation, with the M11 functional, of the wave function overlap method to compute effective electronic couplings in nucleic acid systems.

Oxalate decarboxylase uses electron hole hopping for catalysis

“…The EHPath program finds the fastest multistep hopping pathways ( 15 ). The required electron transfer parameters V , λ , and were obtained using a square-tunneling barrier model, Marcus’s two-sphere model ( 3 , 79 , 80 ), and the difference in the donor and acceptor redox potentials. The inner-sphere reorganization energy for the Mn(II)/(III) self-exchange reaction was taken from Johnson and Nelson ( 81 ).…”

Correlation between Charge Transport and Base Excision Repair in the MutY–DNA Glycosylase

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“…That is, the final CT step is irreversible. This irreversibility models rapid scavenging of the excess charge by redox agents in the cell or trapping of the charge on the terminal acceptor. ,, …”

Improving Suppression of Hemipteran Vectors and Bacterial Pathogens of Citrus and Solanaceous Plants: Advances in Antisense Oligonucleotides (FANA)

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