Virus classification Structure Replication Youhua xie(谢幼华) MOH&MOE Key Lab of Medical Molecular Virology Shanghai Medical College, Fudan University 复旦大学上海医学院 分子病毒学教育部/卫生部重点实验室 yhxie@fudan.edu.cn
Virus Classification, Structure & Replication Youhua Xie Youhua Xie (谢幼华 ) MOH&MOE Key Lab of Medical Molecular Virology Sh h i M di l C ll F d U i it Shang h ai M edical C ollege, F u dan U niversit y 复旦大学上海医学院 分子病毒学教育部 /卫生部重点实验室 yhxie@fudan.edu.cn
The nature of viruses Viruses are small infectious agents(diameter 20-300 nm) @ Parvovirus picornavirus Papovavirus Adenovirus Influenza virus Ryan K), Ray Co Herpesvirus Infectious agents smaller than viruses s, prons Giant virus: Mimivirus( 400 nm, genome size 1.2 Mb), Pandoravirus (1 um, genome size 1.9-2. 5 Mb)
The Nature of Viruses Viruses are small infectious agents (diameter 20 ‐300 nm) Infectious agents smaller than viruses: viroids, prions Gi t i an v rus: Mi i i m virus (400 nm, genome size 1.2 Mb), Pandoravirus (1 um, genome size 1.9-2.5 Mb)
The nature of viruses Viruses contain one kind of nucleic acid (dNa or RNa genome) inside a protein shell (capsid), which may be surrounded by a lipid bilayer membrane(envelope). The resulting complete virus particle s called a virion Membrane Matrix prote Nucleocapsid Capsid (icosahedral) ource: Ryan K), Ray CG: Sherris Medical Microbiology, Sth Edition: Copyright o The McGraw-Hill Companies, Inc. All rights reserved
The Nature of Viruses ¾ Viruses Viruses contain contain one kind of nucleic nucleic acid (DNA or RNA genome) inside a protein shell (capsid), which may be surrounded by a lipid bila yer membrane (envelo p e). The resultin g com plete virus particle is called a virion
All Cellular Lives survive in a sea of viruses Viruses are major players in the ecosystem, infecting every cellular life Animals: animal viruses Plants: plant viruses Archaea: archae viruses Fungi: mycoviruses(真菌病毒) Bacteria: bacteriophages(噬菌体) Viruses constitute a substantial amount of biomass on the earth (eg. there are 1030 bacteriophage particles alone in waters on the earth) 1 phage weighs about 1 femtogram(10-15 gram) 1030 phages weigh about =10-15 x 1030= 1015 gram 10 kilogram 109 tons
All Cellular Lives Survive in a Sea of Viruses ¾ Viruses are major players in the ecosystem infecting every Viruses are major players in the ecosystem, infecting every cellular life z Animals: animal viruses z Plants: plant viruses z Archaea: archae viruses z Fungi: mycoviruses （真菌病毒 ） z Bacteria: bacteriophages (噬菌体 ） z …… ¾ Viruses constitute a substantial amount of biomass on the earth ( th 1030 (eg. there are 10 b t i h ti l l i t th 30 bac teriop hage parti cles alone in wa ters on the earth) 1 phage weighs about 1 femtogram (10-15 1 phage weighs about 1 femtogram (10 gram ) 1030 phages weigh about = 10-15 x 1030 = 1015 gram = 1012 kilogram = 109 tons
Viruses are obligate cellular Parasites Viruses multiplicate(replicate) inside host cells Viruses utilize cellular machineries for replication synthesis of proteins synthesis of membranes synthesis of amino acid, carbohydrates and lipids generatation of energy
Viruses Are Obligate Cellular Parasites ¾ Viruses multiplicate (replicate) inside host cells ¾ Viruses utilize cell l u ar machi i ner es for repli ti ca on z synthesis of proteins z synthesis of membranes z synthesis of amino acid, carbohydrates and lipids z generatation of energy