T4 Phage Replication

A T4 bacteriophage arrives in a colony of E. coli. After the virus recognizes and binds to a host cell using receptor binding domains on its tail fibers that recognize bacterial surface epitopes, its tail sheath contracts, injecting its dsDNA (orange) into the cell cytoplasm.
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The DNA is transcribed to RNA, which then shuts down normal processes in the cell and instead directs the synthesis of viral proteins inside the bacterium. Some of these proteins self-assemble to package new DNA and form as many as several hundred new bacteriophages.

At this point the RNA directs the synthesis of endolysins which rupture the host cell membrane from the inside, liberating new bacteriophages to start the cycle again if they encounter another host cell.
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Bacteriophages were used extensively in the Soviet Union to treat bacterial infections while western medicine progressed along a different track with antibiotics. Since the breakup in 1989, former Soviet block countries began using antibiotics instead since at the time they were seen as a magic bullet and it was not clear that antibiotic resistance would reduce their effectiveness in the long term.
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Now with widespread antibiotic resistance and no new classes of antimicrobial molecules on the horizon, the consensus is that bacteriophages may be a credible alternative antimicrobial therapy.
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Protein structure references:
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T4 Baseplate:
PDB ID: 5IV5
Taylor, N.M. et al. (2016) Structure of the T4 baseplate and its function in triggering sheath contraction. Nature 533: 346-352
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T4 Capsid:
EMD ID: 6323
Sun, L. et al. (2015) Cryo-EM structure of the bacteriophage T4 portal protein assembly at near-atomic resolution. Nat Commun 6, 7548
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T4 Tail sheath:
PDB ID: 3FOH
Aksyuk et al. (2009) The tail sheath structure of bacteriophage T4: a molecular machine for infecting bacteria. EMBO J 28(7):821-9

Видео T4 Phage Replication канала Larry O'Connell