VIRION
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Non-enveloped, head-tail structure. The prolate head is about 140 nm in length and 70 nm in width. The tail is contractile, has 6 long terminal fibers, 6 short spikes and a small base plate.
GENOME
Linear, dsDNA genome of about 170-245 kb, encoding for 300-415 proteins.
GENE EXPRESSION
Genes are transcribed by operons.
REPLICATION
CYTOPLASMIC
- Adsorption: the phage attaches to the target cell through its tail fibers.
- Viral exolysin degrades host cell wall locally.
- Ejection of the viral DNA into host cell cytoplasm by contraction of the tail sheath.
- Transcription and translation of early genes.
- Replication of genomic DNA. Transcription and translation of late genes.
- Assembly of an empty procapsid and packaging of the genome.
- Viral tail fibers assembly and viral tail assembly.
- Mature virions are released from the cell by lysis.