Nonenveloped, head-tail structure. The head is about 60 nm in diameter. The long tail is non-contractile and has 6 fibers although some siphoviruses have only 3 or 4. The capsid is icosahedral with a T=7 symmetry.
Linear, dsDNA genome of about 50 kb, containing about 70 genes.
- Adsorption: the phage attaches to target cell through its tail fibers.
- Viral lysozyme degrades cell wall locally
- Injection: viral DNA is injected in host cell periplasm
- DNA genome is circularized or integrated into host chromosome
- Transcription and translation of early genes
- Replication of genomic DNA
- Transcription and translation of late genes
- Assembly of new virions in host cell cytoplasm
- Mature virions are released from the cell by lysis