VIRION
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Non-enveloped, head-tail structure with Myo-type morphology. The icosahedral head is about 60 nm, with a T=7 dextro symmetry , composed of 72 capsomers. The tail is contractile, about 135 x 18 nm, has 6 short kinked fibers.
GENOME
Linear, dsDNA genome of about 34 kb, encoding for approximately 45 proteins. The genome has cohesive ends (cos sites).
GENE EXPRESSION
Genes are transcribed by operons.
ENZYMES
- Serine protease (Peptidase S73)
- Integrase
REPLICATION
CYTOPLASMIC
- Adsorption: the phage attaches to the target cell through its tail fibers.
- Ejection of the viral DNA into host cell cytoplasm by contraction of the tail sheath.
- Transcription and translation of early genes.
- Synthesis of linear concatemers copies of viral DNA by rolling circle. 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.