Biophysical Journal 55: 243-253 (1989)
© 1989 the Biophysical Society

This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Baker, T S Articles by Bina, M Search for Related Content PubMed PubMed Citation Articles by Baker, T S Articles by Bina, M

The capsid of small papova viruses contains 72 pentameric capsomeres: direct evidence from cryo-electron-microscopy of simian virus 40.

Department of Biological Sciences, Purdue University, West Lafayette, Indiana 47907.

ABSTRACT

The three-dimensional structure of the simian virus 40 capsid is remarkably similar to the structure of the polyoma empty capsid. This similarity is apparent despite striking differences in the methods used to determine the two structures: image analysis of electron micrographs of frozen-hydrated samples (SV40 virions) and an unconventional x-ray crystallographic analysis (polyoma empty capsids). Both methods have clearly resolved the 72 prominent capsomere units which comprise the T = 7d icosahedral capsid surface lattice. The 12 pentavalent and 60 hexavalent capsomeres consist of pentameric substructures. A pentameric morphology for hexavalent capsomeres clearly shows that the conserved bonding specificity expected from the quasi-equivalence theory is not present in either SV40 or polyoma capsids. Determination of the SV40 structure from cryo-electron microscopy supports the correctness of the polyoma structure solved crystallographically and establishes a strong complementarity of the two techniques. Similarity between the SV40 virion and the empty polyoma capsid indicates that the capsid is not detectably altered by the loss of the nucleohistone core. The unexpected pentameric substructure of the hexavalent capsomeres and the arrangement of the 72 pentamers in the SV40 and polyoma capsid lattices may be characteristic features of all members of the papova virus family, including the papilloma viruses such as human wart and rabbit papilloma.

This article has been cited by other articles:

				J. Nilsson, N. Miyazaki, L. Xing, B. Wu, L. Hammar, T. C. Li, N. Takeda, T. Miyamura, and R. H. Cheng Structure and Assembly of a T=1 Virus-Like Particle in BK Polyomavirus J. Virol., May 1, 2005; 79(9): 5337 - 5345. [Abstract] [Full Text] [PDF]

				T. S. Baker, N. H. Olson, and S. D. Fuller Adding the Third Dimension to Virus Life Cycles: Three-Dimensional Reconstruction of Icosahedral Viruses from Cryo-Electron Micrographs Microbiol. Mol. Biol. Rev., December 1, 1999; 63(4): 862 - 922. [Abstract] [Full Text] [PDF]

				M. Li, P. Beard, P. A. Estes, M. K. Lyon, and R. L. Garcea Intercapsomeric Disulfide Bonds in Papillomavirus Assembly and Disassembly J. Virol., March 1, 1998; 72(3): 2160 - 2167. [Abstract] [Full Text] [PDF]

				J. R. Caston, B. L. Trus, F. P. Booy, R. B. Wickner, J. S. Wall, and A. C. Steven Structure of L-A Virus: A Specialized Compartment for the Transcription and Replication of Double-stranded RNA J. Cell Biol., September 8, 1997; 138(5): 975 - 985. [Abstract] [Full Text] [PDF]

				A. Zlotnick, N. Cheng, S. J. Stahl, J. F. Conway, A. C. Steven, and P. T. Wingfield Localization of the C terminus of the assembly domain of hepatitis B virus capsid protein: Implications for morphogenesis and organization of encapsidated RNA PNAS, September 2, 1997; 94(18): 9556 - 9561. [Abstract] [Full Text] [PDF]