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S A ELLISON

Publications and source records attributed to S A ELLISON.

At least 19 recordsLinked to original sources

T1 bacteriophage production in Escherichia coli

Feiner, Rose R. (Columbia University, New York, N.Y.) and Solon A. Ellison. T1 bacteriophage production in Escherichia coli. J. Bacteriol. 85:7-11. 1963.-Progeny released from complexes formed between unirradiated Escherichia coli strain Bs-1 and ultraviolet (UV)-irradiated phage T1 were equally infective for strains B and Bs-1, and were therefore not hostmodified. The capacity of Bs-1 for unirradiated or irradiated T1 is relatively insensitive to UV irradiation, as compared with that of strains B and B/r. In all three strains of E. coli, B, B/r, and Bs-1, the UV sensitivity of the capacity for phage T1 is independent of the UV sensitivity of colony-forming ability. These findings are discussed in relation to the partial genetic homology hypothesis.

Coliphages↗

Structure and development of viruses observed in the electron microscope. II. Vaccinia and fowl pox viruses.

Vaccinia and fowl pox viruses were visualized by the electron microscope in sections of infected chorioallantoic membrane of chicken embryos. The viruses were of similar structure and size, averaging 200 x 300 mmicro with considerable individual variation. Intracytoplasmic viral particles contained a dense, nucleus-like body (nucleoid) separated from granular material (viroplasm) by a zone of lesser density. They were enclosed by a single membrane. Near the surface of the host cell and in the extracellular space the particles consisted of a central body of variable shape and density enclosed by a double membrane. The initial sites of development were confined to the cytoplasm of the host cell. Before release from the host cell the viral nucleoids appeared to enlarge and to occupy a central position within the particle, which became enclosed by a double limiting membrane. The brick-shaped forms found after removal of the embedding plastic from thick sections indicated that drying caused characteristic distortion of certain viral particles.

Animals↗

Structure and development of viruses as observed in the electron microscope. I. Herpes simplex virus.

Herpes simplex virus was visualized by the electron microscope in sections of infected chorioallantoic membrane of chicken embryos. Removal of the embedding methacrylate from relatively thick sections permitted large numbers of viral particles to be seen but caused extensive alteration of cellular components as well as variable distortion of viral structure. This distortion was characterized by disruption of particles and loss of central bodies, resulting in ring or empty shell forms. An inner structure of the virus was revealed in ultrathin sections from which the embedding plastic was not removed. The nuclei of infected cells contained small, dense, primary bodies (30 to 40 mmicro in diameter) as well as slightly larger and less dense particles (40 to 50 mmicro in diameter) surrounded by a single membrane (70 to 100 mmicro in diameter). In the cytoplasm most of the particles possessed a double outer membrane (120 to 130 mmicro in diameter). It is suggested that the initial site of viral development is restricted to the nucleus where primary bodies form and become enclosed by a single outer membrane. Upon release into the cytoplasm these particles appear to acquire a second outer membrane and presumably represent the mature virus.

Animals↗