Abstract
Structure factor amplitudes and phases can be computed directly from electron cryomicroscopy images. Inherent aberrations of the electromagnetic lenses and other instrumental factors affect the structure factors, however, resulting in decreased accuracy in the determined three-dimensional reconstruction. In contrast, solution x-ray scattering provides absolute and accurate measurement of spherically averaged structure factor amplitudes of particles in solution but does not provide information on the phases. In the present study, we explore the merits of using solution x-ray scattering data to estimate the imaging parameters necessary to make corrections to the structure factor amplitudes derived from electron cryomicroscopic images of icosahedral virus particles. Using 400-kV spot-scan images of the bacteriophage P22 procapsid, we have calculated an amplitude contrast of 8.0 +/- 5.2%. The amplitude decay parameter has been estimated to be 523 +/- 188 A2 with image noise compensation and 44 +/- 66 A2 without it. These results can also be used to estimate the minimum number of virus particles needed for reconstruction at different resolutions.
Full Text
The Full Text of this article is available as a PDF (298.9 KB).
Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- Adrian M., Dubochet J., Lepault J., McDowall A. W. Cryo-electron microscopy of viruses. Nature. 1984 Mar 1;308(5954):32–36. doi: 10.1038/308032a0. [DOI] [PubMed] [Google Scholar]
- Aubrey K. L., Casjens S. R., Thomas G. J., Jr Secondary structure and interactions of the packaged dsDNA genome of bacteriophage P22 investigated by Raman difference spectroscopy. Biochemistry. 1992 Dec 1;31(47):11835–11842. doi: 10.1021/bi00162a023. [DOI] [PubMed] [Google Scholar]
- Avila-Sakar A. J., Chiu W. Visualization of beta-sheets and side-chain clusters in two-dimensional periodic arrays of streptavidin on phospholipid monolayers by electron crystallography. Biophys J. 1996 Jan;70(1):57–68. doi: 10.1016/S0006-3495(96)79597-8. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Blaurock A. E. Bacteriorhodospin: a trans-membrane pump containing alpha-helix. J Mol Biol. 1975 Apr 5;93(2):139–158. doi: 10.1016/0022-2836(75)90124-2. [DOI] [PubMed] [Google Scholar]
- Brink J., Chiu W. Contrast analysis of cryo-images of n-paraffin recorded at 400 kV out to 2.1 A resolution. J Microsc. 1991 Feb;161(Pt 2):279–295. doi: 10.1111/j.1365-2818.1991.tb03090.x. [DOI] [PubMed] [Google Scholar]
- Bullough P. A., Tulloch P. A. High-resolution spot-scan electron microscopy of microcrystals of an alpha-helical coiled-coil protein. J Mol Biol. 1990 Sep 5;215(1):161–173. doi: 10.1016/s0022-2836(05)80101-9. [DOI] [PubMed] [Google Scholar]
- Böttcher B., Crowther R. A. Difference imaging reveals ordered regions of RNA in turnip yellow mosaic virus. Structure. 1996 Apr 15;4(4):387–394. doi: 10.1016/s0969-2126(96)00044-5. [DOI] [PubMed] [Google Scholar]
- Böttcher B., Wynne S. A., Crowther R. A. Determination of the fold of the core protein of hepatitis B virus by electron cryomicroscopy. Nature. 1997 Mar 6;386(6620):88–91. doi: 10.1038/386088a0. [DOI] [PubMed] [Google Scholar]
- Conway J. F., Cheng N., Zlotnick A., Wingfield P. T., Stahl S. J., Steven A. C. Visualization of a 4-helix bundle in the hepatitis B virus capsid by cryo-electron microscopy. Nature. 1997 Mar 6;386(6620):91–94. doi: 10.1038/386091a0. [DOI] [PubMed] [Google Scholar]
- Downing K. H., Chiu W. Cold stage design for high resolution electron microscopy of biological materials. Electron Microsc Rev. 1990;3(2):213–226. doi: 10.1016/0892-0354(90)90002-a. [DOI] [PubMed] [Google Scholar]
- Downing K. H. Spot-scan imaging in transmission electron microscopy. Science. 1991 Jan 4;251(4989):53–59. doi: 10.1126/science.1846047. [DOI] [PubMed] [Google Scholar]
- Dubochet J., Adrian M., Chang J. J., Homo J. C., Lepault J., McDowall A. W., Schultz P. Cryo-electron microscopy of vitrified specimens. Q Rev Biophys. 1988 May;21(2):129–228. doi: 10.1017/s0033583500004297. [DOI] [PubMed] [Google Scholar]
- Earnshaw W. C., Harrison S. C. DNA arrangement in isometric phage heads. Nature. 1977 Aug 18;268(5621):598–602. doi: 10.1038/268598a0. [DOI] [PubMed] [Google Scholar]
- Earnshaw W., Casjens S., Harrison S. C. Assembly of the head of bacteriophage P22: x-ray diffraction from heads, proheads and related structures. J Mol Biol. 1976 Jun 25;104(2):387–410. doi: 10.1016/0022-2836(76)90278-3. [DOI] [PubMed] [Google Scholar]
- Frank J. Averaging of low exposure electron micrographs of non-periodic objects. Ultramicroscopy. 1975 Dec;1(2):159–162. doi: 10.1016/s0304-3991(75)80020-9. [DOI] [PubMed] [Google Scholar]
- Glaeser R. M., Downing K. H. Assessment of resolution in biological electron crystallography. Ultramicroscopy. 1992 Nov;47(1-3):256–265. doi: 10.1016/0304-3991(92)90201-t. [DOI] [PubMed] [Google Scholar]
- Glaeser R. M. Limitations to significant information in biological electron microscopy as a result of radiation damage. J Ultrastruct Res. 1971 Aug;36(3):466–482. doi: 10.1016/s0022-5320(71)80118-1. [DOI] [PubMed] [Google Scholar]
- Greene B., King J. Scaffolding mutants identifying domains required for P22 procapsid assembly and maturation. Virology. 1996 Nov 1;225(1):82–96. doi: 10.1006/viro.1996.0577. [DOI] [PubMed] [Google Scholar]
- Grimes J. M., Jakana J., Ghosh M., Basak A. K., Roy P., Chiu W., Stuart D. I., Prasad B. V. An atomic model of the outer layer of the bluetongue virus core derived from X-ray crystallography and electron cryomicroscopy. Structure. 1997 Jul 15;5(7):885–893. doi: 10.1016/s0969-2126(97)00243-8. [DOI] [PubMed] [Google Scholar]
- Harrison S. C. Structure of tomato bushy stunt virus. I. The spherically averaged electron density. J Mol Biol. 1969 Jun 28;42(3):457–483. doi: 10.1016/0022-2836(69)90236-8. [DOI] [PubMed] [Google Scholar]
- Henderson R. Image contrast in high-resolution electron microscopy of biological macromolecules: TMV in ice. Ultramicroscopy. 1992 Oct;46(1-4):1–18. doi: 10.1016/0304-3991(92)90003-3. [DOI] [PubMed] [Google Scholar]
- Henderson R. The potential and limitations of neutrons, electrons and X-rays for atomic resolution microscopy of unstained biological molecules. Q Rev Biophys. 1995 May;28(2):171–193. doi: 10.1017/s003358350000305x. [DOI] [PubMed] [Google Scholar]
- Henderson R. The structure of the purple membrane from Halobacterium hallobium: analysis of the X-ray diffraction pattern. J Mol Biol. 1975 Apr 5;93(2):123–138. doi: 10.1016/0022-2836(75)90123-0. [DOI] [PubMed] [Google Scholar]
- Jack A., Harrison S. C., Crowther R. A. Structure of tomato bushy stunt virus. II. Comparison of results obtained by electron microscopy and x-ray diffraction. J Mol Biol. 1975 Sep 15;97(2):163–172. doi: 10.1016/s0022-2836(75)80032-5. [DOI] [PubMed] [Google Scholar]
- Jack A., Harrison S. C. On the interpretation of small-angle x-ray solution scattering from spherical viruses. J Mol Biol. 1975 Nov 25;99(1):15–25. doi: 10.1016/s0022-2836(75)80155-0. [DOI] [PubMed] [Google Scholar]
- Jeng T. W., Chiu W., Zemlin F., Zeitler E. Electron imaging of crotoxin complex thin crystal at 3.5 A. J Mol Biol. 1984 May 5;175(1):93–97. doi: 10.1016/0022-2836(84)90449-2. [DOI] [PubMed] [Google Scholar]
- Jeng T. W., Crowther R. A., Stubbs G., Chiu W. Visualization of alpha-helices in tobacco mosaic virus by cryo-electron microscopy. J Mol Biol. 1989 Jan 5;205(1):251–257. doi: 10.1016/0022-2836(89)90379-3. [DOI] [PubMed] [Google Scholar]
- Maniatis T., Venable J. H., Jr, Lerman L. S. The structure of psi DNA. J Mol Biol. 1974 Mar 25;84(1):37–64. doi: 10.1016/0022-2836(74)90211-3. [DOI] [PubMed] [Google Scholar]
- Mimori Y., Yamashita I., Murata K., Fujiyoshi Y., Yonekura K., Toyoshima C., Namba K. The structure of the R-type straight flagellar filament of Salmonella at 9 A resolution by electron cryomicroscopy. J Mol Biol. 1995 May 26;249(1):69–87. doi: 10.1006/jmbi.1995.0281. [DOI] [PubMed] [Google Scholar]
- PAULING L., COREY R. B. The structure of hair, muscle, and related proteins. Proc Natl Acad Sci U S A. 1951 May;37(5):261–271. doi: 10.1073/pnas.37.5.261. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Perkins G. A., Downing K. H., Glaeser R. M. Crystallographic extraction and averaging of data from small image areas. Ultramicroscopy. 1995 Sep;60(2):283–294. doi: 10.1016/0304-3991(95)00063-5. [DOI] [PubMed] [Google Scholar]
- Prasad B. V., Prevelige P. E., Marietta E., Chen R. O., Thomas D., King J., Chiu W. Three-dimensional transformation of capsids associated with genome packaging in a bacterial virus. J Mol Biol. 1993 May 5;231(1):65–74. doi: 10.1006/jmbi.1993.1257. [DOI] [PubMed] [Google Scholar]
- Prevelige P. E., Jr, Thomas D., King J. Scaffolding protein regulates the polymerization of P22 coat subunits into icosahedral shells in vitro. J Mol Biol. 1988 Aug 20;202(4):743–757. doi: 10.1016/0022-2836(88)90555-4. [DOI] [PubMed] [Google Scholar]
- Prevelige P. E., Jr, Thomas D., King J., Towse S. A., Thomas G. J., Jr Conformational states of the bacteriophage P22 capsid subunit in relation to self-assembly. Biochemistry. 1990 Jun 12;29(23):5626–5633. doi: 10.1021/bi00475a030. [DOI] [PubMed] [Google Scholar]
- Roberts M. M., White J. L., Grütter M. G., Burnett R. M. Three-dimensional structure of the adenovirus major coat protein hexon. Science. 1986 May 30;232(4754):1148–1151. doi: 10.1126/science.3704642. [DOI] [PubMed] [Google Scholar]
- Schmid M. F., Matsudaira P., Jeng T. W., Jakana J., Towns-Andrews E., Bordas J., Chiu W. Crystallographic analysis of acrosomal bundle from Limulus sperm. J Mol Biol. 1991 Sep 20;221(2):711–725. doi: 10.1016/0022-2836(91)80082-6. [DOI] [PubMed] [Google Scholar]
- Shaw A. L., Rothnagel R., Chen D., Ramig R. F., Chiu W., Prasad B. V. Three-dimensional visualization of the rotavirus hemagglutinin structure. Cell. 1993 Aug 27;74(4):693–701. doi: 10.1016/0092-8674(93)90516-S. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Sherman M. B., Brink J., Chiu W. Performance of a slow-scan CCD camera for macromolecular imaging in a 400 kV electron cryomicroscope. Micron. 1996 Apr;27(2):129–139. doi: 10.1016/0968-4328(96)00018-2. [DOI] [PubMed] [Google Scholar]
- Smith M. F., Langmore J. P. Quantitation of molecular densities by cryo-electron microscopy. Determination of the radial density distribution of tobacco mosaic virus. J Mol Biol. 1992 Aug 5;226(3):763–774. doi: 10.1016/0022-2836(92)90631-s. [DOI] [PubMed] [Google Scholar]
- Stewart P. L., Burnett R. M., Cyrklaff M., Fuller S. D. Image reconstruction reveals the complex molecular organization of adenovirus. Cell. 1991 Oct 4;67(1):145–154. doi: 10.1016/0092-8674(91)90578-m. [DOI] [PubMed] [Google Scholar]
- Stewart P. L., Fuller S. D., Burnett R. M. Difference imaging of adenovirus: bridging the resolution gap between X-ray crystallography and electron microscopy. EMBO J. 1993 Jul;12(7):2589–2599. doi: 10.1002/j.1460-2075.1993.tb05919.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Thomas G. J., Jr, Li Y., Fuller M. T., King J. Structural studies of P22 phage, precursor particles, and proteins by laser Raman spectroscopy. Biochemistry. 1982 Aug 3;21(16):3866–3878. doi: 10.1021/bi00259a023. [DOI] [PubMed] [Google Scholar]
- Thuman-Commike P. A., Chiu W. PTOOL: a software package for the selection of particles from electron cryomicroscopy spot-scan images. J Struct Biol. 1996 Jan-Feb;116(1):41–47. doi: 10.1006/jsbi.1996.0008. [DOI] [PubMed] [Google Scholar]
- Thuman-Commike P. A., Greene B., Jakana J., Prasad B. V., King J., Prevelige P. E., Jr, Chiu W. Three-dimensional structure of scaffolding-containing phage p22 procapsids by electron cryo-microscopy. J Mol Biol. 1996 Jul 5;260(1):85–98. doi: 10.1006/jmbi.1996.0383. [DOI] [PubMed] [Google Scholar]
- Toyoshima C., Unwin N. Contrast transfer for frozen-hydrated specimens: determination from pairs of defocused images. Ultramicroscopy. 1988;25(4):279–291. doi: 10.1016/0304-3991(88)90003-4. [DOI] [PubMed] [Google Scholar]
- Tuma R., Prevelige P. E., Jr, Thomas G. J., Jr Structural transitions in the scaffolding and coat proteins of P22 virus during assembly and disassembly. Biochemistry. 1996 Apr 9;35(14):4619–4627. doi: 10.1021/bi952793l. [DOI] [PubMed] [Google Scholar]
- Unwin N. Nicotinic acetylcholine receptor at 9 A resolution. J Mol Biol. 1993 Feb 20;229(4):1101–1124. doi: 10.1006/jmbi.1993.1107. [DOI] [PubMed] [Google Scholar]
- Unwin P. N., Henderson R. Molecular structure determination by electron microscopy of unstained crystalline specimens. J Mol Biol. 1975 May 25;94(3):425–440. doi: 10.1016/0022-2836(75)90212-0. [DOI] [PubMed] [Google Scholar]
- Zhou Z. H., Hardt S., Wang B., Sherman M. B., Jakana J., Chiu W. CTF determination of images of ice-embedded single particles using a graphics interface. J Struct Biol. 1996 Jan-Feb;116(1):216–222. doi: 10.1006/jsbi.1996.0033. [DOI] [PubMed] [Google Scholar]
- Zhou Z. H., Prasad B. V., Jakana J., Rixon F. J., Chiu W. Protein subunit structures in the herpes simplex virus A-capsid determined from 400 kV spot-scan electron cryomicroscopy. J Mol Biol. 1994 Sep 30;242(4):456–469. doi: 10.1006/jmbi.1994.1594. [DOI] [PubMed] [Google Scholar]
- Zhu J., Penczek P. A., Schröder R., Frank J. Three-dimensional reconstruction with contrast transfer function correction from energy-filtered cryoelectron micrographs: procedure and application to the 70S Escherichia coli ribosome. J Struct Biol. 1997 Apr;118(3):197–219. doi: 10.1006/jsbi.1997.3845. [DOI] [PubMed] [Google Scholar]
- Zlotnick A., Cheng N., Conway J. F., Booy F. P., Steven A. C., Stahl S. J., Wingfield P. T. Dimorphism of hepatitis B virus capsids is strongly influenced by the C-terminus of the capsid protein. Biochemistry. 1996 Jun 11;35(23):7412–7421. doi: 10.1021/bi9604800. [DOI] [PubMed] [Google Scholar]