BIOL 3155 Lecture Notes - Lecture 2: Uranyl Acetate, Negative Stain, Lipid Bilayer
16 Apr 2019
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Document Summary
Basic concepts: virus particle = package virus genomes in infected cells. Rna or dna genome from one cell to another. Outer shell of a virion can be a rigid, symmetrical container called capsid. When the viral nucleic acid genome is package within the capsid, it results in a nucleocapsid structure. Can enclose nucleocapsid in a lipid bilayer membrane = envelope. Reveals the structure of the virion by the exclusion of electron-absorbing molecule like uranyl acetate. Why we need particles: it help to protect viral genome -> Partciles can carry essential enzymes (like rt or rdrp). Are also important for infecting cells: for attachment by receptor binding proteins, for entry by fusion (fusion protein) or for exist by budding (receptor binding proteins or matrix) -> you can proteins and receptors in the particles. Studying virus structure: most structures are too small for light microscope -> ex: mimiviruses (800nm) Tem - to detect shape and surface features (electron microscope), requires staining.
