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CLASSIFICATION

1. Group-ds dna
2. Order-caudovirales
   Family-myxoviridae
3. Genus-T4 like viruses
4. Species- T4 phage
   
5. The t4 phage is a coliphage infecting coliform bacteria like E coli
   Its DNA is 169-170nm long and is enclosed in an icosahedral head.

• the phage contains distict base plate upon which the tail fibres are attached.
• the tail is a hollow tube through which the nuclear materil passes into the host cell.
• the phage is capableof only lytic cycle.
  • 
    INFECTION PROCESS
    
    T4 phage ----------------------------> rcognises cell surface receptors of host with the help of its LTF(long tail fibres)------------------------------->rcognition signal is sent from LTF to base plate----------------------------> unravelling of short tail fibres in response to this signal-----------------------------> STF binds irreversibly to E coli surface----------------------------> due to this the base plate changes conformation and the tail sheath contracts----------------------->causes GPF5( a platelet protein used in the recognition of von willibrand factor here acts as a lysing enzyme) at the end of the tail tube to pucture theouter cell membrane -------------------------------------------->lysozyme domain of GPF5 is activate and itdegrades theperiplasmic peptidoglycan layer----------------->the remaining part of the phage is degraded and the phage is ejected into the ecoli through the tail tube.