Non-enveloped, head-tail structure. The capsid that contains contains an inner body is very large, about 145 nm in diameter, with an icosahedral symmetry T=27. The extended tail measures 160 x 35 nm.


Genomes are about 280 kb in size, are circularly permuted and terminally redundant and have a mosaic structure. They contain about 306 genes.


Genes are transcribed by operons.



  1. Adsorption: the phage attaches to the target cell through its tail fibers.
  2. Ejection of the viral DNA into host cell cytoplasm by contraction of the tail sheath.
  3. Transcription and translation of early genes.
  4. Replication of viral DNA. Transcription and translation of late genes.
  5. Assembly of an empty procapsid and packaging of the genome.
  6. Viral tail fibers assembly and viral tail assembly.
  7. Mature virions are released from the cell by lysis.