Electron Hole Flow Patterns through the RNA-Cleaving 8-17 Deoxyribozyme Yield Unusual Information about Its Structure and Folding

Abstract

DNA double helices have been shown to conduct electron holes over significant distances. Here, we report on the hole flow patterns within a more intricately folded DNA complex, the 8-17 deoxyribozyme bound to a DNA pseudosubstrate, incorporating three helical elements and two catalytically relevant loops. The observed hole flow patterns within the complex permitted a quantitative assessment of the stacking preferences of the three constituent helices and provided evidence for significant transitions within the complex's global geometry. The patterns further suggested varying levels of solvent exposure of the complex's constituent parts, and revealed that a catalytically relevant cytosine within the folded complex exists in an unusual structural/electronic environment. Our data suggest that the study of charge flow may provide novel perspectives on the structure and folding of intricately folded DNAs and RNAs. © 2007 Elsevier Ltd. All rights reserved.