BIO 3153 Lecture Notes - Lecture 9: Martinus Beijerinck, Veterinary Virology, Lipid Bilayer
Document Summary
Beijerinck filtered extract from diseased tobacco plant (1898) Beijerinck named the solution contagium vivum fluidum = contagious living fluid. Head with a helical tail: complex, naked, enveloped. Capsid is protein shell which surrounds and protects the genome. It is built up of multiple (identical) protein sub-units called capsomers. Nucleocapsid refers to the genome plus capsid. Envelope refers to the lipid membrane which surrounds some viruses. It is derived from the plasma membrane of the host cell. Mrna (ribosome ready) is always the plus (+) strand. Dna of equivalent polarity is also the (+) strand. Rna and dna complements of (+) strands are negative (-) strands. Bacterial viruses are easiest to grow (hosts in liquid medium or spread as lawns on agar and inoculated with virus) Animal viruses (and some plant viruses) can be cultivated in tissue cultures (from animal organ in culture medium) Titer refers to the number of infectious units per volume of fluid.
