Non-enveloped, round, T=1 icosahedral symmetry, about 30 nm in diameter. The capsid consists of 12 pentagonal trumpet-shaped pentomers. The virion is composed of 60 copies each of the F, G, and J proteins, and 12 copies of the H protein. There are 12 spikes which are each composed of 5 G and one H proteins.


Circular, ssDNA genome (+) of 4.4 to 6.1kb. replication occurs via dsDNA intermediate and rolling circle.


Early and late genes promoters tightly regulates the timing of gene expression, which is crucial for the replication cycle.



  1. The viral particle attaches to host cell by binding host lipopolysaccharides.
  2. The proteins of the capsid perform Injection of the viral DNA through bacterial membranes into cell cytoplasm.
  3. Host polymerase convert the (+)ssDNA viral genome into a covalently closed dsDNA called replicative form DNA I (RF-I).
  4. Early viral genes are transcribed by host RNA polymerase, producing viral replication proteins.
  5. Viral protein A cleaves RF-I(+) DNA strand at the origin of replication and covalently attaches itself to the DNA.
  6. (+)strand replication occurs by rolling circle, which is converted to dsDNA by host polymerase, generating RF-II molecules (amplification of RF-I).
  7. Late viral genes are transcribed by host RNA polymerase.
  8. Procapsid assembly in the cytoplasm.
  9. Viral protein C binds to replication complex, inducing synthesis and packaging of neo-synthesized (+)ssDNA genomes (RF-III) into procapsids.
  10. Procapsids maturation occurs in host cytoplasm
  11. Mature virions are released from the cell by lysis.

Matching UniProtKB/Swiss-Prot entries

8 entries grouped by strain (browse by keywords)

8 entries

Chlamydia phage 1 (Bacteriophage Chp1) reference strain

REP_BPCHP Replication-associated protein ORF4 (EC 3.1.21.-) (EC (Rep)
ORF7_BPCHP Uncharacterized protein ORF7
ORF6_BPCHP Uncharacterized protein ORF6
C_BPCHP Protein ORF5
B_BPCHP Internal scaffolding protein VP3 (Protein VP3) (VP3)
CAPSD_BPCHP Capsid protein VP1 (Protein VP1) (VP1)
H_BPCHP Minor spike protein H (H protein) (Pilot protein) (Protein VP2) (VP2)
J_BPCHP DNA binding protein ORF8