Wednesday, 30 March, 2011
Single-Molecule Four-Color FRET Visualizes Energy-Transfer Paths on DNA Origami
I. H. Stein, C. Steinhauer, and P. Tinnefeld -
J. Am. Chem. Soc., Vol. 133 (12), pp. 4193–4195 (2011)
Fluorescence resonance energy transfer (FRET) represents a mechanism to transport light energy at the nanoscale, as exemplified by nature’s light-harvesting complexes. Here we used DNA origami to arrange fluorophores that transport excited-state energy from an input dye to an output dye. We demonstrate that energy-transfer paths can be controlled on the single-molecule level by the presence of a “jumper” dye that directs the excited-state energy either to a red or to an IR output dye. We used single-molecule four-color FRET with alternating laser excitation to sort subpopulations and to visualize the control of energy transfer.