Mnemonic to simplify virus classification
Mnemonic to simplify virus classification :
First , we have 2 rules :
Naked virus is Nasty compared with enveloped ( N=N) WHY ?
1) outside the body : more resistant and inactivated by formalin ( not by lipid solvent ether)
2) enter the body by all means ( not only direct contact)
3) exit the body by lysis of cell ( not budding )
N or N -------> NN
All dNa or Naked RNA virus ------> twiNN & twiNNy = icosahedral ( icosanoids=20 carbons ) ( we can ignore pox and retro and consider them icosahedral for simplicity).
So All helical ----------> RNA & enveloped.
we can deduce that most of RNA are helical and enveloped with exceptions.
also most of RNA are single stranded and undergo cytoplasmic replications ( in eukaryotes . RNA is single stranded and all three types exit into the cytoplasm.)
Now we can make 6 rules with exceptions ( supplemented with mnemonics )
1) ~~~ = strand
All are single stranded except 1
Reo ( coz it's the smallest ) .
2) = replication into two .
All replicate in cytoplasm ( many marry in extraordinary way but a couple of retro= old fashion and ortho= tidy marry in ordinary way)
3) = envelop cover is triangle ( usually) .
we talk about RNA . if we want to make amplified segments PCR ----> I must extract it from nuclear envelop.
All are enveloped except PCR which are naked ( and Nasty)
( to make more simple imagine RNA come out of nucleus to cytoplasm and enveloped with nuclear envelop)
P= picorna , C = calici , R= reo.
* when we symbolize r, we choose the smallest reo not retro
* paramyxo doen't come alone. if it comes, it must accompany orthomyxo ( p comes with o ) , so if we see p alone, it's picorna.
4) = square (4) is segmented into 4 . blood group A, B , R ( antigens) or none 0.
and rbc may be segmented (hemolysed)
All are intact except 4 are segmented A= arena , B= bunya, O= orthomyxo , R= reo ( of course)
and segments are ( 2,3,8,11) respectively.
5) S = shape ( 5 is similar to S ) helical or icosahedral .
to visualize and be sure of shape we enhance transcription by PCR + TF ( transcription factor )
All are helical ( helix is similar to S and RNA shape is helix )
except PCR + T= toga and F= flavi which are icosahedral.
please notice that PCR are naked viruses , so they must be icosahedral.
( filo comes with rhabdo coz filo and rhabdo are fillet & flesh !! both comes with bunya = beans )
6) sex ( fertility F= +/- ) ( also x in sex and + )
Actulally half = 6 are + , the other half=6 are - and reo is double standed = neutral.
All are + ( reo =0 ) except :
again to replicate we have a start point at cetain Base Pairs and this is considered as Origin oF Replication
Origin oF Replication And Base Pair
O=orthomyxo , F= filo , R= rhabdo , A= arena, B= bunya , P= paramyxo .
Note that numbers (1,2,3,4,5,6) reflect number of exceptions.
we take about RNA. so we talk about replication and transcription and so on.
Actually the only one who follows tha all 6 rules is corona . that's way its name was not mentioned b4.
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