Medical Microbiology

&Tineacorporis(ringworm):MicrosporumcanisandTrichophytonmenta- grophytes.Affectshairlessskin. &Tineapedis(athlete’sfoot) ...

IV Virology HerpessimplexVirus Kayser, Medical Microbiology © 2005 Thieme ...

7 GeneralVirology K.A.Bienz Definition &VirusesarecomplexesconsistingofproteinandanRNAorDNAgenome. Theylackbothcellularstruc ...

MorphologyandStructure 377 componentsofnewvirusesinaccordancewiththegeneticinformationit contains.Onethusmightcallviruses“vagabo ...

378 7 GeneralVirology onthefamily;thenucleicacidofRNAvirusesisusuallysingle-stranded(ss), withtheexceptionofthereoviruses,andisa ...

MorphologyandStructure 379 OtherComponentsofViralParticles Variousenzymes.Virusesrequireanumberofdifferentenzymesdependingon gen ...

380 7 GeneralVirology Classification &Thetaxonomicsystemusedforvirusesisartificial(i.e.,itdoesnotreflect virusevolution)andi ...

Replication 381 Theoriginsandevolutionofthevirusesarestilllargelyinthedark.Incontrast tothetaxonomicsystemsusedtoclassifythehigh ...

382 7 GeneralVirology Table 7. 2 Tax onom y of the Viruses Nu cl ei c acid N uc le o- cap sid sy mmetr y En velop e Virusdiam et ...

Replication 383 24 -^30 ss(+) Picornaviridae Ent ero virus Polio virus, ec ho virus, co xsac kie viruses Hepa to virus Hepa titi ...

384 7 GeneralVirology Adsorption.Virusparticlescanonlyinfectcellspossessingsurface“recep- tors”specifictotheparticularvirusspeci ...

Replication 385 Hepadnaviruses:thegenomeconsistsofanssDNAantisensestrandanda shortsensestrand(Fig. 7 .5e).Theinfectedcelltranscr ...

386 7 GeneralVirology ReplicationoftheViralGenome + + + + + + + + Polymerase Polymerase a + – Polymerase Polymerase ...

ViralProteinSynthesis 387 ViralProteinSynthesis ProductionofviralmRNA.InaDNAvirusinfection,cellularpolymerases transcribemRNAint ...

388 7 GeneralVirology Theactualproteinsynthesisprocedureisimplemented,codedbytheviral mRNA,withthehelpofcellularcomponentssuchas ...

Genetics 389 Genetics &Justasinhigherlifeforms,viralgeneticmaterialissubjecttochangeby mutation.Lackofacorrectivereplication ...

390 7 GeneralVirology Mutation.Mutationsarechangesinthebasesequenceofanucleicacid,re- sultinginamoreorlessradicalalterationofthe ...

Genetics 391 NongeneticInteractions Inmixedinfectionsbytwo(ormore)viruses,variousviralcomponentscanbe exchangedortheymaycompleme ...

392 7 GeneralVirology tion,travel,andhumanincursionintoisolatedbiotopes(examplesinclude theEbola,RiftValleyfever,WestNile,pulmon ...

Host-CellReactions 393 tonecroticcytopathy,theirprimarypurposeistosupportspecificstepsin viralsynthesis.Forexample,RNAsynthesisa ...