Tequatrovirus

VIRION

Non-enveloped, head-tail structure. The prolate head is 120 nm in length and 86 nm in width. The tail is contractile, has 6 long terminal fibers, 6 short spikes and a small base plate. The capsid has an elongated icosahedral symmetry T=13 Q=21, composed of 152 capsomers .

GENOME

Linear, dsDNA genome of about 169 kb, encoding for approximately 300 proteins.

GENE EXPRESSION

Genes are transcribed by operons.

REPLICATION

CYTOPLASMIC

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