Casadabanvirus

VIRION

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Non-enveloped, head-tail structure. The icosahedral head is about 40 nm in diameter. The non-contractile tail is about 190 nm in length.

GENOME

Linear dsDNA genome of about 37 kb, containing about 55 genes. Bacterial DNA is covalently linked at the left and the right end of the viral genome. The presence of these pieces of bacterial DNA is due to the headful packaging mechanism.

GENE EXPRESSION

REPLICATION

CYTOPLASMIC

  1. Adsorption: The phage attaches to target cell adhesion receptors through its tail fibers.
  2. Ejection of the viral DNA into host cell cytoplasm by long flexible tail ejection system.
  3. Transcription and translation of early genes
  4. Circularization and supercoiling of the viral DNA.
  5. Integration of viral DNA into the host chromosome.
  6. Replicative transposition gives rise to new copies of the viral genome in the host chromosome.
  7. Transcription and translation of late genes.
  8. Assembly of an empty procapsid and headful packaging of the genome.
  9. Viral tail fiber assembly and viral tail assembly.
  10. Mature virions are released from the cell by lysis.