HSCI 338 Lecture Notes - Lecture 1: Icosahedral Symmetry, Tobacco Mosaic Virus, Intracellular Parasite

• School: Simon Fraser University
• Department: Health Sciences
• Course: HSCI 338
• Professor: Nienke Van Houten

Document Summary

Lecture 1: defi(cid:374)e (cid:448)i(cid:396)us a(cid:374)d des(cid:272)(cid:396)i(cid:271)e its disti(cid:374)guishi(cid:374)g featu(cid:396)es. Virus particles are produced from the assembly of pre formed components, not by division. They are absolutely dependent on the host cell for energy. Robert koch: germ theory, proof for a causative agent of an infectious disease. Iwanowski and beijerinck: tobacco mosaic virus pass through a filter. Loeffler and frosch: food and mouth disease. Virions are assembled and stabilized by physicochemical forces. The particle is in the free energy minimum state: hydrophobic and electrostatic interactions. Covalent bonds are rarely involved in holding the multiple subunits together: protein-protein, protein-nucleic acid, and protein-lipid interactions, identify and explain the two basic shapes that are used to produce viral structures, helical capsids- always enveloped. Composed of helical nucleocapsid + additional layers of protein and lipid. Number of unit triangles on each of the 20 triangular faces of icosahedron.