Acknowledgments
Part of this work was supported by NIH grant HL090630 (ISK)
and an SREB Fellowship (KN).
References
1. Henderson R, Unwin PN (1975) Threedimensional model of purple membrane
obtained by electron microscopy. Nature 257
(5521):28–32
2. Henderson R, Baldwin JM, Ceska TA,
Zemlin F, Beckmann E, Downing KH (1990)
Model for the structure of bacteriorhodopsin
based on high-resolution electron cryomicroscopy. J Mol Biol 213(4):899–929
3. Wang DN, Ku ¨hlbrandt W, Fujiyoshi Y (1994)
Atomic model of plant light-harvesting complex by electron crystallography. Nature 367
(6464):614–621
4. Nogales E, Wolf SG, Downing KH (1998)
Structure of the alpha beta tubulin dimer by
electron crystallography. Nature 391:199–203
5. Lo ¨we J, Li H, Downing KH, Nogales E (2001)
Refined structure of alpha beta-tubulin at 3.5 A
resolution. J Mol Biol 313:1045–1057
6. Gonen T, Cheng Y, Sliz P, Hiroaki Y,
Fujiyoshi Y, Harrison SC, Walz T (2005)
Lipid-protein interactions in double-layered
two-dimensional AQP0 crystals. Nature 438
(7068):633–638
7. Ku ¨hlbrandt W (2014) The resolution revolution. Science 343(6178):1443–1444
8. Efremov RG, Gatsogiannis C, Raunser S
(2017) Lipid nanodiscs as a tool for highresolution structure determination of membrane proteins by single-particle cryo-EM.
Methods Enzymol 594:1–30
9. Sun C, Gennis RB (2019) Single-particle cryoEM studies of transmembrane proteins in SMA
copolymer nanodiscs. Chem Phys Lipids
221:114–119
10. Nannenga BL, Gonen T (2018) MicroED: a
versatile cryoEM method for structure determination. Emerg Top Life Sci 2(1):1–8
11. Martynowycz MW, Zhao W, Hattne J, Jensen
GJ, Gonen T (2019) Collection of continuous
rotation microed data from ion beam-milled
crystals of any size. Structure 27(3):545–548
12. Jap BK, Zulauf M, Scheybani T, Hefti A,
Baumeister W, Aebi U, Engel A (1992) 2D
crystallization: from art to science. Ultramicroscopy 46:45–84
13. Ku ¨hlbrandt W (1992) Two-dimensional crystallization of membrane proteins. Q Rev Biophys 25:1–49
14. Stahlberg H, Fotiadis D, Scheuring S,
Re ´migy H, Braun T, Mitsuoka K, Fujiyoshi Y,
Engel A (2001) Two-dimensional crystals: a
powerful approach to assess structure, function
and dynamics of membrane proteins. FEBS
Lett 504:166–172
15. Mosser G (2001) Two-dimensional crystallogenesis of transmembrane proteins. Micron
32:517–540
16. Ku ¨hlbrandt W (2003) In: Sch€ agger H, Hunte
C (eds) Membrane protein purification and
crystallization: a practical approach, 2nd edn.
Academic Press, San Diego, pp 253–284
17. Schmidt-Krey I (2007) Electron crystallography of membrane proteins: two-dimensional
crystallization and screening by electron
microscopy. Methods 41(4):417–426
18. Signorell GA, Kaufmann TC, Kukulski W,
Engel A, Re ´migy HW (2007) Controlled 2D
crystallization of membrane proteins using
methyl-betacyclodextrin. J Struct Biol 157
(2):321–328
19. Vink M, Derr KD, Love J, Stokes DL,
Ubarretxena-Belandia I (2007) A high
throughput strategy to screen 2D crystallization trials of membrane proteins. J Struct Biol
160(3):295–304
20. Johnson MC, Schmidt-Krey I (2013)
Two-dimensional crystallization by dialysis for
structural studies of membrane proteins by the
cryo-EM method electron crystallography.
Methods Cell Biol 113:325–337
21. Uddin YM, Schmidt-Krey I (2015) Inducing
two-dimensional crystallization of membrane
proteins by dialysis for electron crystallography.
Methods Enzymol 557:351–362
22. Ku ¨hlbrandt W, Downing KH (1989)
Two-dimensional structure of plant light harvesting complex at 3.7
A resolution by electron crystallography. J Mol Biol 207:823–826
23. Wang DN, Ku ¨hlbrandt W (1991) Highresolution electron crystallography of lightharvesting chlorophyll a/b-protein complex
in three different media. J Mol Biol 217
(4):691–699
244
Matthew C. Johnson et al.
Part of this work was supported by NIH grant HL090630 (ISK)
and an SREB Fellowship (KN).
References
1. Henderson R, Unwin PN (1975) Threedimensional model of purple membrane
obtained by electron microscopy. Nature 257
(5521):28–32
2. Henderson R, Baldwin JM, Ceska TA,
Zemlin F, Beckmann E, Downing KH (1990)
Model for the structure of bacteriorhodopsin
based on high-resolution electron cryomicroscopy. J Mol Biol 213(4):899–929
3. Wang DN, Ku ¨hlbrandt W, Fujiyoshi Y (1994)
Atomic model of plant light-harvesting complex by electron crystallography. Nature 367
(6464):614–621
4. Nogales E, Wolf SG, Downing KH (1998)
Structure of the alpha beta tubulin dimer by
electron crystallography. Nature 391:199–203
5. Lo ¨we J, Li H, Downing KH, Nogales E (2001)
Refined structure of alpha beta-tubulin at 3.5 A
resolution. J Mol Biol 313:1045–1057
6. Gonen T, Cheng Y, Sliz P, Hiroaki Y,
Fujiyoshi Y, Harrison SC, Walz T (2005)
Lipid-protein interactions in double-layered
two-dimensional AQP0 crystals. Nature 438
(7068):633–638
7. Ku ¨hlbrandt W (2014) The resolution revolution. Science 343(6178):1443–1444
8. Efremov RG, Gatsogiannis C, Raunser S
(2017) Lipid nanodiscs as a tool for highresolution structure determination of membrane proteins by single-particle cryo-EM.
Methods Enzymol 594:1–30
9. Sun C, Gennis RB (2019) Single-particle cryoEM studies of transmembrane proteins in SMA
copolymer nanodiscs. Chem Phys Lipids
221:114–119
10. Nannenga BL, Gonen T (2018) MicroED: a
versatile cryoEM method for structure determination. Emerg Top Life Sci 2(1):1–8
11. Martynowycz MW, Zhao W, Hattne J, Jensen
GJ, Gonen T (2019) Collection of continuous
rotation microed data from ion beam-milled
crystals of any size. Structure 27(3):545–548
12. Jap BK, Zulauf M, Scheybani T, Hefti A,
Baumeister W, Aebi U, Engel A (1992) 2D
crystallization: from art to science. Ultramicroscopy 46:45–84
13. Ku ¨hlbrandt W (1992) Two-dimensional crystallization of membrane proteins. Q Rev Biophys 25:1–49
14. Stahlberg H, Fotiadis D, Scheuring S,
Re ´migy H, Braun T, Mitsuoka K, Fujiyoshi Y,
Engel A (2001) Two-dimensional crystals: a
powerful approach to assess structure, function
and dynamics of membrane proteins. FEBS
Lett 504:166–172
15. Mosser G (2001) Two-dimensional crystallogenesis of transmembrane proteins. Micron
32:517–540
16. Ku ¨hlbrandt W (2003) In: Sch€ agger H, Hunte
C (eds) Membrane protein purification and
crystallization: a practical approach, 2nd edn.
Academic Press, San Diego, pp 253–284
17. Schmidt-Krey I (2007) Electron crystallography of membrane proteins: two-dimensional
crystallization and screening by electron
microscopy. Methods 41(4):417–426
18. Signorell GA, Kaufmann TC, Kukulski W,
Engel A, Re ´migy HW (2007) Controlled 2D
crystallization of membrane proteins using
methyl-betacyclodextrin. J Struct Biol 157
(2):321–328
19. Vink M, Derr KD, Love J, Stokes DL,
Ubarretxena-Belandia I (2007) A high
throughput strategy to screen 2D crystallization trials of membrane proteins. J Struct Biol
160(3):295–304
20. Johnson MC, Schmidt-Krey I (2013)
Two-dimensional crystallization by dialysis for
structural studies of membrane proteins by the
cryo-EM method electron crystallography.
Methods Cell Biol 113:325–337
21. Uddin YM, Schmidt-Krey I (2015) Inducing
two-dimensional crystallization of membrane
proteins by dialysis for electron crystallography.
Methods Enzymol 557:351–362
22. Ku ¨hlbrandt W, Downing KH (1989)
Two-dimensional structure of plant light harvesting complex at 3.7
A resolution by electron crystallography. J Mol Biol 207:823–826
23. Wang DN, Ku ¨hlbrandt W (1991) Highresolution electron crystallography of lightharvesting chlorophyll a/b-protein complex
in three different media. J Mol Biol 217
(4):691–699
244
Matthew C. Johnson et al.