Mass analysis of bacteriophage T4 proheads and mature heads by scanning transmission electron microscopy and hydrodynamic measurements.

Quantitative mass analysis of bacteriophage T4 proheads by scanning transmission electron microscopy (STEM) revealed a mass of 79.5 +/- 0.6 MDa, while hydrodynamic measurements yielded a prohead mass of about 80 MDa. This is 25% less than the prohead mass deduced from its polypeptide composition, and this finding implies that the bacteriophage T4 prohead is built of fewer polypeptide copies than previously reported. In contrast, the mass of mature heads measured by STEM, 194 +/- 2 MDa, is in agreement with previous mass measurements of DNA and protein content, and it is consistent with the previously determined stoichiometry. This good agreement of average STEM values for proheads and mature heads with corresponding hydrodynamic measurements suggests that STEM allows faithful evaluation of the masses of large supramolecular assemblies (i.e., greater than or equal to 200 MDa) such as whole viruses or cellular organelles.

[1]  T. Hohn,et al.  Stages of bacteriophage lambda head morphogenesis: physical analysis of particles in solution. , 1978, Journal of molecular biology.

[2]  D. Freifelder.  Molecular weights of coliphages and coliphage DNA. IV. Molecular weights of DNA from bacteriophages T4, T5 and T7 and the general problem of determination of M. , 1970, Journal of molecular biology.

[3]  A. Engel,et al.  Gene 20 product of bacteriophage T4 its purification and structure. , 1981, Journal of molecular biology.

[4]  E. Buhle,et al.  Correlation between structure and mass distribution of the nuclear pore complex and of distinct pore complex components , 1990, The Journal of cell biology.

[5]  U. K. Laemmli,et al.  Maturation of the head of bacteriophage T4. I. DNA packaging events. , 1973, Journal of molecular biology.

[6]  N. Davidson,et al.  Electron microscope heteroduplex study of sequence relations of T2, T4, and T6 bacteriophage DNAs. , 1974, Virology.

[7]  M. Yanagida,et al.  Molecular organization of the shell of the Teven bacteriophage head. , 1975, Journal of molecular biology.

[8]  D. Lang,et al.  Molecular weights of coliphages and coliphage DNA. 3. Contour length and molecular weight of DNA from bacteriophages T4, T5 and T7, and from bovine papilloma virus. , 1970, Journal of molecular biology.

[9]  O. H. Lowry,et al.  Protein measurement with the Folin phenol reagent. , 1951, The Journal of biological chemistry.

[10]  D. Freifelder,et al.  Molecular weights of coliphages and coliphage DNA. I. Measurement of the molecular weight of bacteriophage T7 by high-speed equilibrium centrifugation. , 1970, Journal of molecular biology.

[11]  R. Edgar,et al.  Some steps in the assembly of bacteriophage T4. , 1968, Journal of molecular biology.

[12]  G. Benedek,et al.  Molecular weights of coliphages and colip- hage DNA. II. Measurement of diffusion coefficients using optical mixing spectroscopy, and measurement of sedimentation coefficients. , 1970, Journal of molecular biology.

[13]  A. Engel,et al.  The Structure and Characterization of a Closterovirus, Beet Yellows Virus, and a Luteovirus, Beet Mild Yellowing Virus, by Scanning Transmission Electron Microscopy, Optical Diffraction of Electron Images and Acrylamide Gel Electrophoresis , 1983 .

[14]  A. Engel,et al.  Monte Carlo calculations of elastic and inelastic electron scattering in biological and plastic materials , 1984 .

[15]  A. Steven,et al.  Capsid fine structure of T-even bacteriophages. Binding and localization of two dispensable capsid proteins into the P23* surface lattice. , 1977, Journal of molecular biology.

[16]  M. Showe,et al.  Isolation and characterization of bacteriophage T4 mutant preheads , 1978, Journal of virology.

[17]  M. Showe,et al.  Localization of minor protein components of the head of bacteriophage T4 , 1977, Journal of virology.

[18]  C. Schmid,et al.  Molecular weights of homogeneous coliphage DNA's from density-gradient sedimentation equilibrium. , 1969, Journal of molecular biology.

[19]  M F Moody,et al.  The shape of the T-even bacteriophage head. , 1965, Virology.

[20]  S. Colowick,et al.  Methods in Enzymology , Vol , 1966 .

[21]  J. Wall,et al.  Scanning transmission electron microscopic study of molluscan hemocyanins in various aggregation states: comparison with light scattering molecular weights. , 1989, Journal of ultrastructure and molecular structure research.

[22]  L. Black.  Ahmad-Zadeh C,+AHMADAAZADEH C: Internal proteins of bacteriophage T4D: their characterization and relation to head structure and assembly. , 1971, Journal of molecular biology.

[23]  E. Kellenberger,et al.  Aberrant forms of the T-even phage head. , 1965, Virology.

[24]  A. Engel,et al.  Preparation of unstained protein structures for mass determination by electron scattering. , 1980, Journal of ultrastructure research.

[25]  B L Trus,et al.  Mass and molecular composition of vesicular stomatitis virus: a scanning transmission electron microscopy analysis , 1985, Journal of virology.

[26]  L Landmann,et al.  Head structure of bacteriophages T2 and T4. , 1988, Journal of ultrastructure and molecular structure research.

[27]  M. Zulauf,et al.  Self-assembly of brome mosaic virus protein into capsids. Initial and final states of aggregation. , 1983, Journal of Molecular Biology.

[28]  A. Lustig,et al.  Molecular weight determination of labile structures: a variant of the sedimentation-diffusion method. , 1978, Journal of molecular biology.

[29]  U. Aebi,et al.  Structural changes during the transformation of bacteriophage T4 polyheads: characterization of the initial and final states by freeze-drying and shadowing Fab-fragment-labelled preparations. , 1978, Journal of molecular biology.

[30]  U. K. Laemmli,et al.  Cleavage of Structural Proteins during the Assembly of the Head of Bacteriophage T4 , 1970, Nature.

[31]  M. Showe,et al.  Gene 21 protein-dependent proteolysis in vitro of purified gene 22 product of bacteriophage T4. , 1975, Journal of molecular biology.