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Single-Molecule FRET: Principles and Analysis

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Fluorescence Spectroscopy and Microscopy in Biology

Part of the book series: Springer Series on Fluorescence ((SS FLUOR,volume 20))

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Abstract

Förster resonance energy transfer (FRET) is a powerful spectroscopic technique to study conformational changes of nucleic acids and proteins and their molecular interactions. When combined with a single-molecule approach, FRET has the distinct advantage that it can monitor the conformational heterogeneity and dynamics of individual molecules and enable the observation of short-lived molecular intermediates usually hidden in ensemble experiments. This in turn makes single-molecule FRET an interesting tool for dynamic structural biology.

This chapter presents the principles of single-molecule FRET spectroscopy and the added information it gives compared to ensemble FRET spectroscopy. We describe different experimental implementations, primarily focusing on intensity-based approaches. Fluorescence from single molecules requires careful experimental procedures to maximize the inherently low signal intensity, and meticulous data analysis, which is introduced in this chapter, to quantify FRET detection. We comment on advantages and limitations of the technique, and its strength is illustrated by two application examples.

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References

  1. van den Bedem H, Fraser J (2015) Integrative, dynamic structural biology at atomic resolution–it’s about time. Nat Methods 12:307–318. https://doi.org/10.1038/NMETH.3324

    Article  PubMed  Google Scholar 

  2. Förster T (1948) Zwischenmolekulare Energiewanderung und Fluoreszenz. Ann Phys 437:55–75. https://doi.org/10.1002/andp.19484370105

    Article  Google Scholar 

  3. Stryer L, Hauglandt RP (1967) Energy transfer: a spectroscopic ruler. Proc Natl Acad Sci U S A 58:719. https://doi.org/10.1073/pnas.58.2.719

    Article  CAS  PubMed  Google Scholar 

  4. Latt SA, Cheung T, Blout ER (1964) Energy transfer. A system with relatively fixed donor-acceptor separation. J Am Chem Soc 87:995–1003. https://doi.org/10.1021/ja01083a011

    Article  Google Scholar 

  5. Clegg RM (1992) Fluorescence resonance energy transfer and nucleic acids. Methods Enzymol 211:353–388. https://doi.org/10.1016/0076-6879(92)11020-j

    Article  CAS  PubMed  Google Scholar 

  6. Haas E (2005) The study of protein folding and dynamics by determination of intramolecular distance distributions and their fluctuations using ensemble and single-molecule FRET measurements. ChemPhysChem 6:858–870. https://doi.org/10.1002/cphc.200400617

    Article  CAS  PubMed  Google Scholar 

  7. Haas E, Wilchek M, Katchalski-Katzir E, Steinberg IZ (1975) Distribution of end-to-end distances of oligopeptides in solution as estimated by energy transfer. Proc Natl Acad Sci U S A 72:1807–1811. https://doi.org/10.1073/pnas.72.5.1807

    Article  CAS  PubMed  Google Scholar 

  8. Grinvald A, Haas E, Steinberg IZ (1972) Evaluation of the distribution of distances between energy donors and acceptors by fluorescence decay. Proc Natl Acad Sci 69:2273–2277. https://doi.org/10.1073/pnas.69.8.2273

    Article  CAS  PubMed  Google Scholar 

  9. Tinoco I, Gonzalez RL (2011) Biological mechanisms, one molecule at a time. Genes Dev 25:1205–1231. https://doi.org/10.1101/GAD.2050011

    Article  CAS  PubMed  Google Scholar 

  10. Gopich IV, Szabo A (2012) Theory of the energy transfer efficiency and fluorescence lifetime distribution in single-molecule FRET. Proc Natl Acad Sci U S A 109:7747–7752. https://doi.org/10.1073/pnas.1205120109

    Article  PubMed  Google Scholar 

  11. Hellenkamp B, Schmid S, Doroshenko O et al (2018) Precision and accuracy of single-molecule FRET measurements – a multi-laboratory benchmark study. Nat Methods 15:669–676. https://doi.org/10.1038/s41592-018-0085-0

    Article  CAS  PubMed  Google Scholar 

  12. Ha T, Enderle T, Ogletree DF et al (1996) Probing the interaction between two single molecules: fluorescence resonance energy transfer between a single donor and a single acceptor. Proc Natl Acad Sci U S A 93:6264–6268. https://doi.org/10.1073/pnas.93.13.6264

    Article  CAS  PubMed  Google Scholar 

  13. Bacic L, Sabantsev A, Deindl S (2020) Recent advances in single-molecule fluorescence microscopy render structural biology dynamic. Curr Opin Struct Biol 65:61–68. https://doi.org/10.1016/J.SBI.2020.05.006

    Article  CAS  PubMed  Google Scholar 

  14. Lerner E, Barth A, Hendrix J et al (2021) FRET-based dynamic structural biology: challenges, perspectives and an appeal for open-science practices. elife 10:1–69. https://doi.org/10.7554/eLife.60416

    Article  Google Scholar 

  15. Lerner E, Cordes T, Ingargiola A et al (2018) Toward dynamic structural biology: two decades of single-molecule Förster resonance energy transfer. Science 359(6373):eaan1133. https://doi.org/10.1126/science.aan1133

    Article  CAS  PubMed  Google Scholar 

  16. Sanders JC, Holmstrom ED (2021) Integrating single-molecule FRET and biomolecular simulations to study diverse interactions between nucleic acids and proteins. Essays Biochem 65:37–49. https://doi.org/10.1042/EBC20200022

    Article  CAS  PubMed  Google Scholar 

  17. Walter NG, Huang CY, Manzo AJ, Sobhy MA (2008) Do-it-yourself guide: how to use the modern single-molecule toolkit. Nat Methods 5:475–489. https://doi.org/10.1038/nmeth.1215

    Article  CAS  PubMed  Google Scholar 

  18. Sustarsic M, Kapanidis AN (2015) Taking the ruler to the jungle: single-molecule FRET for understanding biomolecular structure and dynamics in live cells. Curr Opin Struct Biol 34:52–59. https://doi.org/10.1016/j.sbi.2015.07.001

    Article  CAS  PubMed  Google Scholar 

  19. Asher WB, Geggier P, Holsey MD et al (2021) Single-molecule FRET imaging of GPCR dimers in living cells. Nat Methods 18:397–405. https://doi.org/10.1038/s41592-021-01081-y

    Article  CAS  PubMed  Google Scholar 

  20. Fenwick RB, Esteban-Martín S, Salvatella X (2011) Understanding biomolecular motion, recognition, and allostery by use of conformational ensembles. Eur Biophys J 40(12):1339–1355. https://doi.org/10.1007/S00249-011-0754-8

    Article  CAS  PubMed  Google Scholar 

  21. Fisette O, Lagüe P, Gagné S, Morin S (2012) Synergistic applications of MD and NMR for the study of biological systems. J Biomed Biotechnol. https://doi.org/10.1155/2012/254208

  22. Zhong D (2007) Ultrafast catalytic processes in enzymes. Curr Opin Chem Biol 11:174–181. https://doi.org/10.1016/J.CBPA.2007.02.034

    Article  CAS  PubMed  Google Scholar 

  23. Jaffé HH, Miller AL (1966) The fates of electronic excitation energy. J Chem Educ 43:469–473. https://doi.org/10.1021/ED043P469

    Article  Google Scholar 

  24. Chung HS, Eaton WA (2018) Direct protein folding transition path times from single molecule FRET. Curr Opin Struct Biol 48:30–39. https://doi.org/10.1016/j.sbi.2017.10.007

    Article  CAS  PubMed  Google Scholar 

  25. Kilic S, Felekyan S, Doroshenko O et al (2018) Single-molecule FRET reveals multiscale chromatin dynamics modulated by HP1α. Nat Commun 9. https://doi.org/10.1038/s41467-017-02619-5

  26. Yang O, Ha T (2018) Single-molecule studies of ssDNA-binding proteins exchange. Methods Enzymol 600:463–477. https://doi.org/10.1016/bs.mie.2017.11.017

    Article  CAS  PubMed  Google Scholar 

  27. Craggs TD, Sustarsic M, Plochowietz A et al (2019) Substrate conformational dynamics facilitate structure-specific recognition of gapped DNA by DNA polymerase. Nucleic Acids Res 47:10788–10800. https://doi.org/10.1093/nar/gkz797

    Article  CAS  PubMed  Google Scholar 

  28. De Boer M, Gouridis G, Vietrov R et al (2019) Conformational and dynamic plasticity in substrate-binding proteins underlies selective transport in ABC importers. elife 8. https://doi.org/10.7554/ELIFE.44652

  29. Kapanidis AN, Laurence TA, Nam KL et al (2005) Alternating-laser excitation of single molecules. Acc Chem Res 38:523–533. https://doi.org/10.1021/ar0401348

    Article  CAS  PubMed  Google Scholar 

  30. Beckers M, Drechsler F, Eilert T et al (2015) Quantitative structural information from single-molecule FRET. Faraday Discuss 184:117–129. https://doi.org/10.1039/C5FD00110B

    Article  CAS  PubMed  Google Scholar 

  31. Sindbert S, Kalinin S, Nguyen H et al (2011) Accurate distance determination of nucleic acids via Förster resonance energy transfer: implications of dye linker length and rigidity. J Am Chem Soc 133:2463–2480. https://doi.org/10.1021/ja105725e

    Article  CAS  PubMed  Google Scholar 

  32. Kalinin S, Peulen T, Sindbert S et al (2012) A toolkit and benchmark study for FRET-restrained high-precision structural modeling. Nat Methods 9:1218–1225. https://doi.org/10.1038/nmeth.2222

    Article  CAS  PubMed  Google Scholar 

  33. Kapanidis AN, Weiss S (2002) Fluorescent probes and bioconjugation chemistries for single-molecule fluorescence analysis of biomolecules. J Chem Phys 117:10953–10964. https://doi.org/10.1063/1.1521158

    Article  CAS  Google Scholar 

  34. Zosel F, Holla A, Schuler B (2022) Labeling of proteins for single-molecule fluorescence spectroscopy. Methods Mol Biol 2376:207–233. https://doi.org/10.1007/978-1-0716-1716-8_12

    Article  CAS  PubMed  Google Scholar 

  35. Hanspach G, Trucks S, Hengesbach M (2019) Strategic labelling approaches for RNA single-molecule spectroscopy. RNA Biol 16:1119–1132. https://doi.org/10.1080/1547628620191593093

    Article  PubMed  Google Scholar 

  36. Gust A, Zander A, Gietl A et al (2014) A starting point for fluorescence-based single-molecule measurements in biomolecular research. Molecules 19:15824–15865. https://doi.org/10.3390/molecules191015824

    Article  CAS  PubMed  Google Scholar 

  37. Ha T, Tinnefeld P (2012) Photophysics of fluorescent probes for single-molecule biophysics and super-resolution imaging. Annu Rev-Physchem 63:595–617. https://doi.org/10.1146/ANNUREV-PHYSCHEM-032210-103340

    Article  CAS  Google Scholar 

  38. Hohng S, Lee S, Lee J, Jo MH (2014) Maximizing information content of single-molecule FRET experiments: multi-color FRET and FRET combined with force or torque. Chem Soc Rev 43:1007–1013. https://doi.org/10.1039/c3cs60184f

    Article  CAS  PubMed  Google Scholar 

  39. Kim JY, Kim C, Lee NK (2015) Real-time submillisecond single-molecule FRET dynamics of freely diffusing molecules with liposome tethering. Nat Commun 6:1–9. https://doi.org/10.1038/ncomms7992

    Article  CAS  Google Scholar 

  40. Roy R, Hohng S, Ha T (2008) A practical guide to single-molecule FRET. Nat Methods 5:507–516. https://doi.org/10.1038/nmeth.1208

    Article  CAS  PubMed  Google Scholar 

  41. Chandradoss SD, Haagsma AC, Lee YK et al (2014) Surface passivation for single-molecule protein studies. J Vis Exp:4–11. https://doi.org/10.3791/50549

  42. Paul T, Ha T, Myong S (2021) Regeneration of PEG slide for multiple rounds of single-molecule measurements. Biophys J:1–12. https://doi.org/10.1016/j.bpj.2021.02.031

  43. McCann JJ, Choi UB, Zheng L et al (2010) Optimizing methods to recover absolute FRET efficiency from immobilized single molecules. Biophys J 99:961–970. https://doi.org/10.1016/j.bpj.2010.04.063

    Article  CAS  PubMed  Google Scholar 

  44. Hildebrandt LL, Preus S, Birkedal V (2015) Quantitative single molecule FRET efficiencies using TIRF microscopy. Faraday Discuss 184:131–142. https://doi.org/10.1039/c5fd00100e

    Article  CAS  PubMed  Google Scholar 

  45. Lee NK, Kapanidis AN, Wang Y et al (2005) Accurate FRET measurements within single diffusing biomolecules using alternating-laser excitation. Biophys J 88:2939–2953. https://doi.org/10.1529/biophysj.104.054114

    Article  CAS  PubMed  Google Scholar 

  46. Kapanidis AN, Lee NK, Laurence TA et al (2004) Fluorescence-aided molecule sorting: analysis of structure and interactions by alternating-laser excitation of single molecules. Proc Natl Acad Sci U S A 101:8936–8941. https://doi.org/10.1073/pnas.0401690101

    Article  CAS  PubMed  Google Scholar 

  47. Hohlbein J, Craggs TD, Cordes T (2014) Alternating-laser excitation: single-molecule FRET and beyond. Chem Soc Rev 43:1156–1171. https://doi.org/10.1039/c3cs60233h

    Article  CAS  PubMed  Google Scholar 

  48. Müller BK, Zaychikov E, Bräuchle C, Lamb DC (2005) Pulsed interleaved excitation. Biophys J 89:3508–3522. https://doi.org/10.1529/biophysj.105.064766

    Article  CAS  PubMed  Google Scholar 

  49. Eggeling C, Berger S, Brand L et al (2001) Data registration and selective single-molecule analysis using multi-parameter fluorescence detection. J Biotechnol 86:163–180. https://doi.org/10.1016/S0168-1656(00)00412-0

    Article  CAS  PubMed  Google Scholar 

  50. Rothwell PJ, Berger S, Kensch O et al (2003) Multiparameter single-molecule fluorescence spectroscopy reveals heterogeneity of HIV-1 reverse transcriptase:primer/template complexes. Proc Natl Acad Sci U S A 100:1655–1660. https://doi.org/10.1073/pnas.0434003100

    Article  CAS  PubMed  Google Scholar 

  51. Hohng S, Joo C, Ha T (2004) Single-molecule three-color FRET. Biophys J 87:1328–1337. https://doi.org/10.1529/biophysj.104.043935

    Article  CAS  PubMed  Google Scholar 

  52. Kim E, Lee S, Jeon A et al (2013) A single-molecule dissection of ligand binding to a protein with intrinsic dynamics. Nat Chem Biol 9:313–318. https://doi.org/10.1038/nchembio.1213

    Article  CAS  PubMed  Google Scholar 

  53. Lee J, Lee S, Ragunathan K et al (2010) Single-molecule four-color FRET. Angew Chem Int Ed 49:9922–9925. https://doi.org/10.1002/ANIE.201005402

    Article  CAS  Google Scholar 

  54. Phelps C, Israels B, Marsh MC et al (2016) Using multiorder time-correlation functions (TCFs) to elucidate biomolecular reaction pathways from microsecond single-molecule fluorescence experiments. J Phys Chem B 120:13003–13016. https://doi.org/10.1021/acs.jpcb.6b08449

    Article  CAS  PubMed  Google Scholar 

  55. Santoso Y, Joyce CM, Potapova O et al (2010) Conformational transitions in DNA polymerase I revealed by single-molecule FRET. Proc Natl Acad Sci U S A 107:715–720. https://doi.org/10.1073/pnas.0910909107

    Article  PubMed  Google Scholar 

  56. Chung HS, Gopich IV (2014) Fast single-molecule FRET spectroscopy: theory and experiment. Phys Chem Chem Phys 16:18644–18657. https://doi.org/10.1039/c4cp02489c

    Article  CAS  PubMed  Google Scholar 

  57. Torella JP, Holden SJ, Santoso Y et al (2011) Identifying molecular dynamics in single-molecule fret experiments with burst variance analysis. Biophys J 100:1568–1577. https://doi.org/10.1016/j.bpj.2011.01.066

    Article  CAS  PubMed  Google Scholar 

  58. Kalinin S, Valeri A, Antonik M et al (2010) Detection of structural dynamics by FRET: a photon distribution and fluorescence lifetime analysis of systems with multiple states. J Phys Chem B 114:7983–7995. https://doi.org/10.1021/jp102156t

    Article  CAS  PubMed  Google Scholar 

  59. Gopich I, Szabo A (2005) Theory of photon statistics in single-molecule Förster resonance energy transfer. J Chem Phys 122:14707. https://doi.org/10.1063/1.1812746

    Article  CAS  PubMed  Google Scholar 

  60. Lerner E, Ploetz E, Hohlbein J et al (2016) A quantitative theoretical framework for protein-induced fluorescence enhancement-Förster-type resonance energy transfer (PIFE-FRET). J Phys Chem B 120:6401–6410. https://doi.org/10.1021/acs.jpcb.6b03692

    Article  CAS  PubMed  Google Scholar 

  61. Hwang H, Myong S (2014) Protein induced fluorescence enhancement (PIFE) for probing protein-nucleic acid interactions. Chem Soc Rev 43:1221–1229. https://doi.org/10.1039/c3cs60201j

    Article  CAS  PubMed  Google Scholar 

  62. Bronson JE, Fei J, Hofman JM et al (2009) Learning rates and states from biophysical time series: a Bayesian approach to model selection and single-molecule FRET data. Biophys J 97:3196–3205. https://doi.org/10.1016/j.bpj.2009.09.031

    Article  CAS  PubMed  Google Scholar 

  63. McKinney SA, Joo C, Ha T (2006) Analysis of single-molecule FRET trajectories using hidden Markov modeling. Biophys J 91:1941–1951. https://doi.org/10.1529/biophysj.106.082487

    Article  CAS  PubMed  Google Scholar 

  64. Szoszkiewicz R, Ainavarapu SRK, Wiita AP et al (2008) Dwell time analysis of a single-molecule mechanochemical reaction. Langmuir 24:1356–1364. https://doi.org/10.1021/la702368b

    Article  CAS  PubMed  Google Scholar 

  65. Kinz-Thompson CD, Bailey NA, Gonzalez RL (2016) Precisely and accurately inferring single-molecule rate constants. Methods Enzymol 581:187–225. https://doi.org/10.1016/bs.mie.2016.08.021

    Article  CAS  PubMed  Google Scholar 

  66. Widom JR, Dhakal S, Heinicke LA, Walter NG (2014) Single-molecule tools for enzymology, structural biology, systems biology and nanotechnology: an update. Arch Toxicol 88:1965–1985. https://doi.org/10.1007/s00204-014-1357-9

    Article  CAS  PubMed  Google Scholar 

  67. Tsukanov R, Tomov TE, Liber M et al (2014) Developing DNA nanotechnology using single-molecule fluorescence. Acc Chem Res 47:1789–1798. https://doi.org/10.1021/ar500027d

    Article  CAS  PubMed  Google Scholar 

  68. Bandyopadhyay D, Mishra PP (2021) Decoding the structural dynamics and conformational alternations of DNA secondary structures by single-molecule FRET microspectroscopy. Front Mol Biosci 8:781. https://doi.org/10.3389/FMOLB.2021.725541/BIBTEX

    Article  Google Scholar 

  69. Bochman ML, Paeschke K, Zakian VA (2012) DNA secondary structures: stability and function of G-quadruplex structures. Nat Rev Genet 13:770–780. https://doi.org/10.1038/nrg3296

    Article  CAS  PubMed  Google Scholar 

  70. Aznauryan M, Søndergaard S, Noer SL et al (2016) A direct view of the complex multi-pathway folding of telomeric G-quadruplexes. Nucleic Acids Res 44:11024–11032. https://doi.org/10.1093/nar/gkw1010

    Article  CAS  PubMed  Google Scholar 

  71. Varshney D, Spiegel J, Zyner K et al (2020) The regulation and functions of DNA and RNA G-quadruplexes. Nat Rev Mol Cell Biol 218(21):459–474. https://doi.org/10.1038/s41580-020-0236-x

    Article  CAS  Google Scholar 

  72. GrĂĽn JT, Schwalbe H (2021) Folding dynamics of polymorphic G-quadruplex structures. Biopolymers:e23477. https://doi.org/10.1002/BIP.23477

  73. Šponer J, Bussi G, Stadlbauer P et al (2017) Folding of guanine quadruplex molecules–funnel-like mechanism or kinetic partitioning? An overview from MD simulation studies. Biochim Biophys Acta, Gen Subj 1861:1246–1263. https://doi.org/10.1016/j.bbagen.2016.12.008

    Article  CAS  PubMed  Google Scholar 

  74. Israels B, Albrecht CS, Dang A et al (2021) Submillisecond conformational transitions of short single-stranded DNA lattices by photon correlation single-molecule Förster resonance energy transfer. J Phys Chem B. https://doi.org/10.1021/acs.jpcb.1c04119

  75. Von Hippel PH, Berg OG (1986) On the specificity of DNA-protein interactions. Proc Natl Acad Sci USA 83:1608–1612. https://doi.org/10.1073/pnas.83.6.1608

    Article  Google Scholar 

  76. Hohlbein J, Aigrain L, Craggs TD et al (2013) Conformational landscapes of DNA polymerase i and mutator derivatives establish fidelity checkpoints for nucleotide insertion. Nat Commun 4:1–11. https://doi.org/10.1038/ncomms3131

    Article  CAS  Google Scholar 

  77. Morten MJ, Lopez SG, Emilie Steinmark I et al (2018) Stacking-induced fluorescence increase reveals allosteric interactions through DNA. Nucleic Acids Res 46:11618–11626. https://doi.org/10.1093/nar/gky887

    Article  CAS  PubMed  Google Scholar 

  78. Hohng S, Zhou R, Nahas MK et al (2007) Fluorescence-force spectroscopy maps two-dimensional reaction landscape of the Holliday junction. Science 318:279–283. https://doi.org/10.1126/science.1146113

    Article  CAS  PubMed  Google Scholar 

Download references

Acknowledgments

We thank the reviewer for his/her feedback. We would like to acknowledge support from the Novo Nordisk Foundation (grant NNF20OC0061417) and from the Danish Council for Independent Research (grant DFF-9040-00323B).

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Israels, B., Lund, L.M., Birkedal, V. (2022). Single-Molecule FRET: Principles and Analysis. In: Ĺ achl, R., Amaro, M. (eds) Fluorescence Spectroscopy and Microscopy in Biology. Springer Series on Fluorescence, vol 20. Springer, Cham. https://doi.org/10.1007/4243_2022_32

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