DFT study of the electronic properties of DNA-DNA and PNA-DNA double strands

摘要

The electronic properties of DNA-DNA and PNA-DNA double strands having 3-6 base pairs (bp) were investigated by density functional theory (DFT) calculations. The binding energies and the highest occupied molecular orbital-lowest unoccupied molecular orbital (HOMO-LUMO) energy gaps for the PNA-DNA hybrids in the vapor phase are found to be greater than those for the DNA-DNA hybrids, regardless of the number of base pairs involved. The study supports the experimental finding that PNA displays high affinity toward a complementary DNA and that PNA-DNA strands are much more thermodynamically stable than their DNA-DNA counterparts. The results suggest much higher sensitivity in DNA sequencing with the arrays of PNA than with those of DNA. (c) 2006 Wiley Periodicals, Inc.