Abstract

We investigated fluorescent protein crystals for potential photonic applications, for the first time to our knowledge. Rod-shaped crystals of enhanced green fluorescent protein (EGFP) were synthesized, with diameters of 0.5-2 μm and lengths of 100-200 μm. The crystals exhibit minimal light scattering due to their ordered structure and generate substantially higher fluorescence intensity than EGFP or dye molecules in solutions. The magnitude of concentration quenching in EGFP crystals was measured to be about 7-10 dB. Upon optical pumping at 485 nm, individual EGFP crystals located between dichroic mirrors generated laser emission with a single-mode spectral line at 513 nm. Our results demonstrate the potential of protein crystals as novel optical elements for self-assembled, micro- or nano-lasers and amplifiers in aqueous environment.

© 2014 Optical Society of America

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  1. M. C. Gather and S. H. Yun, “Single-cell biological lasers,” Nat. Photonics 5(7), 406–410 (2011).
    [Crossref]
  2. M. C. Gather and S. H. Yun, “Lasing from Escherichia coli bacteria genetically programmed to express green fluorescent protein,” Opt. Lett. 36(16), 3299–3301 (2011).
    [Crossref] [PubMed]
  3. M. C. Gather and S. H. Yun, “Bio-optimized energy transfer in densely packed fluorescent protein enables near-maximal luminescence and solid-state lasers,” Nat. Commun 5, 5722 (2014).
    [Crossref] [PubMed]
  4. F. Yang, L. G. Moss, and G. N. Phillips., “The molecular structure of green fluorescent protein,” Nat. Biotechnol. 14(10), 1246–1251 (1996).
    [Crossref] [PubMed]
  5. R. Y. Tsien, “The green fluorescent protein,” Annu. Rev. Biochem. 67(1), 509–544 (1998).
    [Crossref] [PubMed]
  6. J. R. Lakowicz, J. Malicka, S. D’Auria, and I. Gryczynski, “Release of the self-quenching of fluorescence near silver metallic surfaces,” Anal. Biochem. 320(1), 13–20 (2003).
    [Crossref] [PubMed]
  7. D. L. Dexter and J. H. Schulman, “Theory of concentration quenching in organizc phosphors,” J. Chem. Phys. 22(6), 1063–1070 (1954).
    [Crossref]
  8. A. Royant, P. Carpentier, J. Ohana, J. McGeehan, B. Paetzold, M. Noirclerc-Savoye, X. Vernede, V. Adam, and D. Bourgeois, “Advances in spectroscopic methods for biological crystals. 1. Fluorescence lifetime measurements,” J. Appl. Cryst. 40(6), 1105–1112 (2007).
    [Crossref]
  9. A. Royant and M. Noirclerc-Savoye, “Stabilizing role of glutamic acid 222 in the structure of enhanced green fluorescent protein,” J. Struct. Biol. 174(2), 385–390 (2011).
    [Crossref] [PubMed]
  10. J. A. J. Arpino, P. J. Rizkallah, and D. D. Jones, “Crystal structure of enhanced green fluorescent protein to 1.35 Å resolution reveals alternative conformations for Glu222,” PLoS ONE 7(10), e47132 (2012).
    [Crossref] [PubMed]
  11. T. Ansbacher, H. K. Srivastava, T. Stein, R. Baer, M. Merkx, and A. Shurki, “Calculation of transition dipole moment in fluorescent proteins--towards efficient energy transfer,” Phys. Chem. Chem. Phys. 14(12), 4109–4117 (2012).
    [Crossref] [PubMed]
  12. M. Ormö, A. B. Cubitt, K. Kallio, L. A. Gross, R. Y. Tsien, and S. J. Remington, “Crystal structure of the Aequorea victoria green fluorescent protein,” Science 273(5280), 1392–1395 (1996).
    [Crossref] [PubMed]
  13. A. Theisen, M. P. Deacon, C. Johann, and S. E. Harding, Refractive Increment Data-Book for Polymer and Biomolecular Scientists (Nottingham University Press, Nottingham, 2000).

2014 (1)

M. C. Gather and S. H. Yun, “Bio-optimized energy transfer in densely packed fluorescent protein enables near-maximal luminescence and solid-state lasers,” Nat. Commun 5, 5722 (2014).
[Crossref] [PubMed]

2012 (2)

J. A. J. Arpino, P. J. Rizkallah, and D. D. Jones, “Crystal structure of enhanced green fluorescent protein to 1.35 Å resolution reveals alternative conformations for Glu222,” PLoS ONE 7(10), e47132 (2012).
[Crossref] [PubMed]

T. Ansbacher, H. K. Srivastava, T. Stein, R. Baer, M. Merkx, and A. Shurki, “Calculation of transition dipole moment in fluorescent proteins--towards efficient energy transfer,” Phys. Chem. Chem. Phys. 14(12), 4109–4117 (2012).
[Crossref] [PubMed]

2011 (3)

A. Royant and M. Noirclerc-Savoye, “Stabilizing role of glutamic acid 222 in the structure of enhanced green fluorescent protein,” J. Struct. Biol. 174(2), 385–390 (2011).
[Crossref] [PubMed]

M. C. Gather and S. H. Yun, “Single-cell biological lasers,” Nat. Photonics 5(7), 406–410 (2011).
[Crossref]

M. C. Gather and S. H. Yun, “Lasing from Escherichia coli bacteria genetically programmed to express green fluorescent protein,” Opt. Lett. 36(16), 3299–3301 (2011).
[Crossref] [PubMed]

2007 (1)

A. Royant, P. Carpentier, J. Ohana, J. McGeehan, B. Paetzold, M. Noirclerc-Savoye, X. Vernede, V. Adam, and D. Bourgeois, “Advances in spectroscopic methods for biological crystals. 1. Fluorescence lifetime measurements,” J. Appl. Cryst. 40(6), 1105–1112 (2007).
[Crossref]

2003 (1)

J. R. Lakowicz, J. Malicka, S. D’Auria, and I. Gryczynski, “Release of the self-quenching of fluorescence near silver metallic surfaces,” Anal. Biochem. 320(1), 13–20 (2003).
[Crossref] [PubMed]

1998 (1)

R. Y. Tsien, “The green fluorescent protein,” Annu. Rev. Biochem. 67(1), 509–544 (1998).
[Crossref] [PubMed]

1996 (2)

F. Yang, L. G. Moss, and G. N. Phillips., “The molecular structure of green fluorescent protein,” Nat. Biotechnol. 14(10), 1246–1251 (1996).
[Crossref] [PubMed]

M. Ormö, A. B. Cubitt, K. Kallio, L. A. Gross, R. Y. Tsien, and S. J. Remington, “Crystal structure of the Aequorea victoria green fluorescent protein,” Science 273(5280), 1392–1395 (1996).
[Crossref] [PubMed]

1954 (1)

D. L. Dexter and J. H. Schulman, “Theory of concentration quenching in organizc phosphors,” J. Chem. Phys. 22(6), 1063–1070 (1954).
[Crossref]

Adam, V.

A. Royant, P. Carpentier, J. Ohana, J. McGeehan, B. Paetzold, M. Noirclerc-Savoye, X. Vernede, V. Adam, and D. Bourgeois, “Advances in spectroscopic methods for biological crystals. 1. Fluorescence lifetime measurements,” J. Appl. Cryst. 40(6), 1105–1112 (2007).
[Crossref]

Ansbacher, T.

T. Ansbacher, H. K. Srivastava, T. Stein, R. Baer, M. Merkx, and A. Shurki, “Calculation of transition dipole moment in fluorescent proteins--towards efficient energy transfer,” Phys. Chem. Chem. Phys. 14(12), 4109–4117 (2012).
[Crossref] [PubMed]

Arpino, J. A. J.

J. A. J. Arpino, P. J. Rizkallah, and D. D. Jones, “Crystal structure of enhanced green fluorescent protein to 1.35 Å resolution reveals alternative conformations for Glu222,” PLoS ONE 7(10), e47132 (2012).
[Crossref] [PubMed]

Baer, R.

T. Ansbacher, H. K. Srivastava, T. Stein, R. Baer, M. Merkx, and A. Shurki, “Calculation of transition dipole moment in fluorescent proteins--towards efficient energy transfer,” Phys. Chem. Chem. Phys. 14(12), 4109–4117 (2012).
[Crossref] [PubMed]

Bourgeois, D.

A. Royant, P. Carpentier, J. Ohana, J. McGeehan, B. Paetzold, M. Noirclerc-Savoye, X. Vernede, V. Adam, and D. Bourgeois, “Advances in spectroscopic methods for biological crystals. 1. Fluorescence lifetime measurements,” J. Appl. Cryst. 40(6), 1105–1112 (2007).
[Crossref]

Carpentier, P.

A. Royant, P. Carpentier, J. Ohana, J. McGeehan, B. Paetzold, M. Noirclerc-Savoye, X. Vernede, V. Adam, and D. Bourgeois, “Advances in spectroscopic methods for biological crystals. 1. Fluorescence lifetime measurements,” J. Appl. Cryst. 40(6), 1105–1112 (2007).
[Crossref]

Cubitt, A. B.

M. Ormö, A. B. Cubitt, K. Kallio, L. A. Gross, R. Y. Tsien, and S. J. Remington, “Crystal structure of the Aequorea victoria green fluorescent protein,” Science 273(5280), 1392–1395 (1996).
[Crossref] [PubMed]

D’Auria, S.

J. R. Lakowicz, J. Malicka, S. D’Auria, and I. Gryczynski, “Release of the self-quenching of fluorescence near silver metallic surfaces,” Anal. Biochem. 320(1), 13–20 (2003).
[Crossref] [PubMed]

Dexter, D. L.

D. L. Dexter and J. H. Schulman, “Theory of concentration quenching in organizc phosphors,” J. Chem. Phys. 22(6), 1063–1070 (1954).
[Crossref]

Gather, M. C.

M. C. Gather and S. H. Yun, “Bio-optimized energy transfer in densely packed fluorescent protein enables near-maximal luminescence and solid-state lasers,” Nat. Commun 5, 5722 (2014).
[Crossref] [PubMed]

M. C. Gather and S. H. Yun, “Single-cell biological lasers,” Nat. Photonics 5(7), 406–410 (2011).
[Crossref]

M. C. Gather and S. H. Yun, “Lasing from Escherichia coli bacteria genetically programmed to express green fluorescent protein,” Opt. Lett. 36(16), 3299–3301 (2011).
[Crossref] [PubMed]

Gross, L. A.

M. Ormö, A. B. Cubitt, K. Kallio, L. A. Gross, R. Y. Tsien, and S. J. Remington, “Crystal structure of the Aequorea victoria green fluorescent protein,” Science 273(5280), 1392–1395 (1996).
[Crossref] [PubMed]

Gryczynski, I.

J. R. Lakowicz, J. Malicka, S. D’Auria, and I. Gryczynski, “Release of the self-quenching of fluorescence near silver metallic surfaces,” Anal. Biochem. 320(1), 13–20 (2003).
[Crossref] [PubMed]

Jones, D. D.

J. A. J. Arpino, P. J. Rizkallah, and D. D. Jones, “Crystal structure of enhanced green fluorescent protein to 1.35 Å resolution reveals alternative conformations for Glu222,” PLoS ONE 7(10), e47132 (2012).
[Crossref] [PubMed]

Kallio, K.

M. Ormö, A. B. Cubitt, K. Kallio, L. A. Gross, R. Y. Tsien, and S. J. Remington, “Crystal structure of the Aequorea victoria green fluorescent protein,” Science 273(5280), 1392–1395 (1996).
[Crossref] [PubMed]

Lakowicz, J. R.

J. R. Lakowicz, J. Malicka, S. D’Auria, and I. Gryczynski, “Release of the self-quenching of fluorescence near silver metallic surfaces,” Anal. Biochem. 320(1), 13–20 (2003).
[Crossref] [PubMed]

Malicka, J.

J. R. Lakowicz, J. Malicka, S. D’Auria, and I. Gryczynski, “Release of the self-quenching of fluorescence near silver metallic surfaces,” Anal. Biochem. 320(1), 13–20 (2003).
[Crossref] [PubMed]

McGeehan, J.

A. Royant, P. Carpentier, J. Ohana, J. McGeehan, B. Paetzold, M. Noirclerc-Savoye, X. Vernede, V. Adam, and D. Bourgeois, “Advances in spectroscopic methods for biological crystals. 1. Fluorescence lifetime measurements,” J. Appl. Cryst. 40(6), 1105–1112 (2007).
[Crossref]

Merkx, M.

T. Ansbacher, H. K. Srivastava, T. Stein, R. Baer, M. Merkx, and A. Shurki, “Calculation of transition dipole moment in fluorescent proteins--towards efficient energy transfer,” Phys. Chem. Chem. Phys. 14(12), 4109–4117 (2012).
[Crossref] [PubMed]

Moss, L. G.

F. Yang, L. G. Moss, and G. N. Phillips., “The molecular structure of green fluorescent protein,” Nat. Biotechnol. 14(10), 1246–1251 (1996).
[Crossref] [PubMed]

Noirclerc-Savoye, M.

A. Royant and M. Noirclerc-Savoye, “Stabilizing role of glutamic acid 222 in the structure of enhanced green fluorescent protein,” J. Struct. Biol. 174(2), 385–390 (2011).
[Crossref] [PubMed]

A. Royant, P. Carpentier, J. Ohana, J. McGeehan, B. Paetzold, M. Noirclerc-Savoye, X. Vernede, V. Adam, and D. Bourgeois, “Advances in spectroscopic methods for biological crystals. 1. Fluorescence lifetime measurements,” J. Appl. Cryst. 40(6), 1105–1112 (2007).
[Crossref]

Ohana, J.

A. Royant, P. Carpentier, J. Ohana, J. McGeehan, B. Paetzold, M. Noirclerc-Savoye, X. Vernede, V. Adam, and D. Bourgeois, “Advances in spectroscopic methods for biological crystals. 1. Fluorescence lifetime measurements,” J. Appl. Cryst. 40(6), 1105–1112 (2007).
[Crossref]

Ormö, M.

M. Ormö, A. B. Cubitt, K. Kallio, L. A. Gross, R. Y. Tsien, and S. J. Remington, “Crystal structure of the Aequorea victoria green fluorescent protein,” Science 273(5280), 1392–1395 (1996).
[Crossref] [PubMed]

Paetzold, B.

A. Royant, P. Carpentier, J. Ohana, J. McGeehan, B. Paetzold, M. Noirclerc-Savoye, X. Vernede, V. Adam, and D. Bourgeois, “Advances in spectroscopic methods for biological crystals. 1. Fluorescence lifetime measurements,” J. Appl. Cryst. 40(6), 1105–1112 (2007).
[Crossref]

Phillips, G. N.

F. Yang, L. G. Moss, and G. N. Phillips., “The molecular structure of green fluorescent protein,” Nat. Biotechnol. 14(10), 1246–1251 (1996).
[Crossref] [PubMed]

Remington, S. J.

M. Ormö, A. B. Cubitt, K. Kallio, L. A. Gross, R. Y. Tsien, and S. J. Remington, “Crystal structure of the Aequorea victoria green fluorescent protein,” Science 273(5280), 1392–1395 (1996).
[Crossref] [PubMed]

Rizkallah, P. J.

J. A. J. Arpino, P. J. Rizkallah, and D. D. Jones, “Crystal structure of enhanced green fluorescent protein to 1.35 Å resolution reveals alternative conformations for Glu222,” PLoS ONE 7(10), e47132 (2012).
[Crossref] [PubMed]

Royant, A.

A. Royant and M. Noirclerc-Savoye, “Stabilizing role of glutamic acid 222 in the structure of enhanced green fluorescent protein,” J. Struct. Biol. 174(2), 385–390 (2011).
[Crossref] [PubMed]

A. Royant, P. Carpentier, J. Ohana, J. McGeehan, B. Paetzold, M. Noirclerc-Savoye, X. Vernede, V. Adam, and D. Bourgeois, “Advances in spectroscopic methods for biological crystals. 1. Fluorescence lifetime measurements,” J. Appl. Cryst. 40(6), 1105–1112 (2007).
[Crossref]

Schulman, J. H.

D. L. Dexter and J. H. Schulman, “Theory of concentration quenching in organizc phosphors,” J. Chem. Phys. 22(6), 1063–1070 (1954).
[Crossref]

Shurki, A.

T. Ansbacher, H. K. Srivastava, T. Stein, R. Baer, M. Merkx, and A. Shurki, “Calculation of transition dipole moment in fluorescent proteins--towards efficient energy transfer,” Phys. Chem. Chem. Phys. 14(12), 4109–4117 (2012).
[Crossref] [PubMed]

Srivastava, H. K.

T. Ansbacher, H. K. Srivastava, T. Stein, R. Baer, M. Merkx, and A. Shurki, “Calculation of transition dipole moment in fluorescent proteins--towards efficient energy transfer,” Phys. Chem. Chem. Phys. 14(12), 4109–4117 (2012).
[Crossref] [PubMed]

Stein, T.

T. Ansbacher, H. K. Srivastava, T. Stein, R. Baer, M. Merkx, and A. Shurki, “Calculation of transition dipole moment in fluorescent proteins--towards efficient energy transfer,” Phys. Chem. Chem. Phys. 14(12), 4109–4117 (2012).
[Crossref] [PubMed]

Tsien, R. Y.

R. Y. Tsien, “The green fluorescent protein,” Annu. Rev. Biochem. 67(1), 509–544 (1998).
[Crossref] [PubMed]

M. Ormö, A. B. Cubitt, K. Kallio, L. A. Gross, R. Y. Tsien, and S. J. Remington, “Crystal structure of the Aequorea victoria green fluorescent protein,” Science 273(5280), 1392–1395 (1996).
[Crossref] [PubMed]

Vernede, X.

A. Royant, P. Carpentier, J. Ohana, J. McGeehan, B. Paetzold, M. Noirclerc-Savoye, X. Vernede, V. Adam, and D. Bourgeois, “Advances in spectroscopic methods for biological crystals. 1. Fluorescence lifetime measurements,” J. Appl. Cryst. 40(6), 1105–1112 (2007).
[Crossref]

Yang, F.

F. Yang, L. G. Moss, and G. N. Phillips., “The molecular structure of green fluorescent protein,” Nat. Biotechnol. 14(10), 1246–1251 (1996).
[Crossref] [PubMed]

Yun, S. H.

M. C. Gather and S. H. Yun, “Bio-optimized energy transfer in densely packed fluorescent protein enables near-maximal luminescence and solid-state lasers,” Nat. Commun 5, 5722 (2014).
[Crossref] [PubMed]

M. C. Gather and S. H. Yun, “Lasing from Escherichia coli bacteria genetically programmed to express green fluorescent protein,” Opt. Lett. 36(16), 3299–3301 (2011).
[Crossref] [PubMed]

M. C. Gather and S. H. Yun, “Single-cell biological lasers,” Nat. Photonics 5(7), 406–410 (2011).
[Crossref]

Anal. Biochem. (1)

J. R. Lakowicz, J. Malicka, S. D’Auria, and I. Gryczynski, “Release of the self-quenching of fluorescence near silver metallic surfaces,” Anal. Biochem. 320(1), 13–20 (2003).
[Crossref] [PubMed]

Annu. Rev. Biochem. (1)

R. Y. Tsien, “The green fluorescent protein,” Annu. Rev. Biochem. 67(1), 509–544 (1998).
[Crossref] [PubMed]

J. Appl. Cryst. (1)

A. Royant, P. Carpentier, J. Ohana, J. McGeehan, B. Paetzold, M. Noirclerc-Savoye, X. Vernede, V. Adam, and D. Bourgeois, “Advances in spectroscopic methods for biological crystals. 1. Fluorescence lifetime measurements,” J. Appl. Cryst. 40(6), 1105–1112 (2007).
[Crossref]

J. Chem. Phys. (1)

D. L. Dexter and J. H. Schulman, “Theory of concentration quenching in organizc phosphors,” J. Chem. Phys. 22(6), 1063–1070 (1954).
[Crossref]

J. Struct. Biol. (1)

A. Royant and M. Noirclerc-Savoye, “Stabilizing role of glutamic acid 222 in the structure of enhanced green fluorescent protein,” J. Struct. Biol. 174(2), 385–390 (2011).
[Crossref] [PubMed]

Nat. Biotechnol. (1)

F. Yang, L. G. Moss, and G. N. Phillips., “The molecular structure of green fluorescent protein,” Nat. Biotechnol. 14(10), 1246–1251 (1996).
[Crossref] [PubMed]

Nat. Commun (1)

M. C. Gather and S. H. Yun, “Bio-optimized energy transfer in densely packed fluorescent protein enables near-maximal luminescence and solid-state lasers,” Nat. Commun 5, 5722 (2014).
[Crossref] [PubMed]

Nat. Photonics (1)

M. C. Gather and S. H. Yun, “Single-cell biological lasers,” Nat. Photonics 5(7), 406–410 (2011).
[Crossref]

Opt. Lett. (1)

Phys. Chem. Chem. Phys. (1)

T. Ansbacher, H. K. Srivastava, T. Stein, R. Baer, M. Merkx, and A. Shurki, “Calculation of transition dipole moment in fluorescent proteins--towards efficient energy transfer,” Phys. Chem. Chem. Phys. 14(12), 4109–4117 (2012).
[Crossref] [PubMed]

PLoS ONE (1)

J. A. J. Arpino, P. J. Rizkallah, and D. D. Jones, “Crystal structure of enhanced green fluorescent protein to 1.35 Å resolution reveals alternative conformations for Glu222,” PLoS ONE 7(10), e47132 (2012).
[Crossref] [PubMed]

Science (1)

M. Ormö, A. B. Cubitt, K. Kallio, L. A. Gross, R. Y. Tsien, and S. J. Remington, “Crystal structure of the Aequorea victoria green fluorescent protein,” Science 273(5280), 1392–1395 (1996).
[Crossref] [PubMed]

Other (1)

A. Theisen, M. P. Deacon, C. Johann, and S. E. Harding, Refractive Increment Data-Book for Polymer and Biomolecular Scientists (Nottingham University Press, Nottingham, 2000).

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Figures (5)

Fig. 1
Fig. 1 EGFP crystals. (a-c) EGFP crystals formed by using trimethylamine hydrochloride (a), sarcosine (b), or manganese (II) chloride tetrahydrate (c). (d-e) EGFP crystals mixed with glass beads dispersed on a glass surface: (d) bright field micrograph; (e) fluorescence image. (f) Z-stack two-photon excited fluorescence image of EGFP crystals. Color represents depth (0-20 µm from green to red). Scale bars, 100 μm.
Fig. 2
Fig. 2 Relative fluorescence intensity of EGFP crystals compared to EGFP solutions. The measurement was corrected for the thickness of each sample. Straight line is a linear extension of the data measured in EGFP solutions and may represent an ideal case without concentration quenching. The concentration in the crystal was assumed to be 15 mM based on the crystal structure. The measurement uncertainty (error bars) for the crystals was relatively large because of their small diameters.
Fig. 3
Fig. 3 Crystal structure. (a) GFP molecule drawn in a cartoon style. The permanent dipole moment (red arrow) is nearly parallel to the short axis of the β-barrel. The transition dipole moment of the fluorophore is at a small angle (~13°) with respect to the long axis of the fluorophore [11]. (b) Illustration of an EGFP crystal in the most probable space group P212121 [12]. (c) Schematic of the EGFP crystal. Green spheres represent individual GFP molecules in the unit cell. For an excited molecule (donor), there are 12 nearest neighbors at similar, although not identical, distances, which can accept the excited state energy via FRET.
Fig. 4
Fig. 4 Schematic of the experimental setup.
Fig. 5
Fig. 5 Laser based on a protein crystal. (a) Laser output energy of a protein-crystal laser as a function of the pump energy; line, linear fit. Inset shows an image of the output emission at pump energy of 280 nJ. Scale bar, 50 μm. (b) Output spectra at two different pump levels of 30 nJ and 280 nJ. The spectral power at 30 nJ is displayed with 100x magnification for easier comparison.

Equations (2)

Equations on this page are rendered with MathJax. Learn more.

k i χ( k R + k NR ),
I=C k R k tot n=0 ( k R,FRET k tot ) n =CQY 1 1+χ

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