VIRION
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Non-enveloped, head-tail structure. The capsid is icosahedral, about 60nm in diameter. The capsid proteins are covalently linked. Tail is flexible, about 135 nm in length and 8 nm in width, with a terminal knob and a single short fiber.
GENOME
Linear, dsDNA genome of about 52 kb, containing about 88 genes. The genome has cohesive ends (cos sites).
GENE EXPRESSION
REPLICATION
CYTOPLASMIC
- Adsorption: The phage attaches to target cell adhesion receptors through its tail fibers.
- Ejection of the viral DNA into host cell cytoplasm by long flexible tail ejection system.
- Transcription and translation of early genes.
- Shutoff of host gene expression, possibly by gp77, gp78 and gp79.
- Replication of genomic DNA by rolling circle.
- Transcription and translation of late genes
- Assembly of an empty procapsid and packaging of the genome.
- Viral tail fiber assembly and viral tail assembly.
- Mature virions are released from the cell by lysis.