Self-Assembled Donor Comprising Quantum Dots and Fluorescent Proteins for Long-Range Fluorescence Resonance Energy Transfer

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• 作者：Huachang Lu ; Oliver Schö ; ps ; Ulrike Woggon ; Christof M. Niemeyer
• 刊名：Journal of the American Chemical Society
• 出版年：2008
• 出版时间：April 9, 2008
• 年：2008
• 卷：130
• 期：14
• 页码：4815 - 4827
• 全文大小：593K
• 年卷期：v.130,no.14(April 9, 2008)
• ISSN：1520-5126

文摘

We report on the development of a self-assembled donor for long-range fluorescence resonanceenergy transfer (FRET). To this end, a three-chromophore FRET (3Ch-FRET) system was constructed,which consists of a luminescent quantum dot (QD), enhanced yellow fluorescent proteins (EYFP), andAtto647-dye-modified oligonucleotides. The system was assembled by electrostatic binding of covalentEYFP-ssDNA conjugate to the QD and subsequent hybridization with complementary oligonucleotideslabeled with Atto647-dye. The final conjugates comprise three different two-chromophore FRET (2Ch-FRET) subsystems, QD/EYFP, QD/Atto647, and EYFP/Atto647, respectively, which were studied in detailby steady-state and time-resolved photoluminescence measurements. The helicity of DNA allowed us tocontrol donor/acceptor separations and thus enabled the detailed analysis of the various FRET processes.We found that the 2Ch-FRET and the 3Ch-FRET (QD/EYFP/Atto647) systems revealed FRET efficienciesand transfer rates that were affected by the availability of distinct FRET pathways. The derived energy-transfer efficiencies and Förster radii indicated that within the 3Ch-FRET system, the 2Ch-FRET subsystemQD/EYFP showed highest FRET efficiencies ranging from 64 to 72%. Thus, it can be used as a powerfuldonor system that combines the intrinsic advantages of QDs (large and spectrally broad absorption crosssection) and EYFP (high quantum yield) and enables long-distance FRET processes for donor-acceptordistances of up to 13 nm.