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 regulate the timing of gene expression, which is crucial for the replication cycle.



  1. Pilus-mediated adsorption of the virus onto host cell
  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

78 entries grouped by strain (browse by keywords)

11 entries

Bdellovibrio phage phiMH2K (Bacteriophage phiMH2K) reference strain

Select_all Deselect_all  
B_BPPHMInternal scaffolding protein VP3
CAPSD_BPPHMCapsid protein VP1 (VP1)
C_BPPHMProtein VP5
H_BPPHMMinor spike protein H (H protein) (Pilot protein) (Protein VP2) (VP2)
J_BPPHMDNA binding protein VP8
N_BPPHMUncharacterized protein N
REP_BPPHMReplication-associated protein VP4 (Rep) (VP4) (EC 3.1.21.-) (EC
W_BPPHMUncharacterized protein W
X_BPPHMUncharacterized protein X
Y_BPPHMUncharacterized protein Y
Z_BPPHMUncharacterized protein Z

10 entries

Enterobacteria phage G4 (Bacteriophage G4) reference strain

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G_BPG4Major spike protein G (G protein) (GPG)
SCAFB_BPG4Internal scaffolding protein B (Scaffolding protein B) (GPB)
SCAFD_BPG4External scaffolding protein D (Scaffolding protein D) (GPD)
VGA_BPG4A protein (GPA)
VGC_BPG4C protein
VGE_BPG4Lysis protein (E protein) (GPE)
VGF_BPG4Capsid protein (F protein) (GPF)
VGH_BPG4Minor spike protein (H protein) (Pilot protein)
VGJ_BPG4Small core protein (J protein)
VGK_BPG4K protein

10 entries

Enterobacteria phage alpha3 (Bacteriophage alpha-3) reference strain

Select_all Deselect_all  
G_BPAL3Major spike protein G (G protein) (GPG)
SCAFB_BPAL3Internal scaffolding protein B (Scaffolding protein B) (GPB)
SCAFD_BPAL3External scaffolding protein D (Scaffolding protein D) (GPD)
VGA_BPAL3A protein (GPA)
VGC_BPAL3C protein
VGE_BPAL3Lysis protein (E protein) (GPE)
VGF_BPAL3Capsid protein (F protein) (GPF)
VGH_BPAL3Minor spike protein (H protein) (Pilot protein)
VGJ_BPAL3Small core protein (J protein)
VGK_BPAL3K protein

10 entries

Enterobacteria phage phiX174 (Isolate Sanger) (Bacteriophage phi-X174) reference strain

Select_all Deselect_all  
CAPSD_BPPHSCapsid protein F (F protein) (GPF)
C_BPPHSProtein C
E_BPPHSLysis protein E (Protein E) (GPE)
G_BPPHSMajor spike protein G (G protein) (GPG)
H_BPPHSMinor spike protein H (H protein) (Pilot protein)
J_BPPHSDNA-binding protein J (Small core protein)
K_BPPHSProtein K
REPA_BPPHSReplication-associated protein A (EC 3.1.21.-) (EC (RepA)
SCAFB_BPPHSInternal scaffolding protein B (Scaffolding protein B) (GPB)
SCAFD_BPPHSExternal scaffolding protein D (Scaffolding protein D) (GPD)

9 entries

Spiroplasma virus 4 (SpV4) reference strain

Select_all Deselect_all  
B_SPV4Internal scaffolding protein ORF3
CAPSD_SPV4Capsid protein VP1 (VP1)
C_SPV4Protein ORF5
H_SPV4Minor spike protein H (H protein) (Pilot protein)
J_SPV4DNA binding protein ORF8
ORF6_SPV4Uncharacterized protein ORF6
ORF7_SPV4Uncharacterized protein ORF7
ORF9_SPV4Uncharacterized protein ORF9
REP_SPV4Replication-associated protein ORF2 (EC 3.1.21.-) (EC (Rep)

8 entries

Chlamydia phage 1 (Bacteriophage Chp1) reference strain

Select_all Deselect_all  
B_BPCHPInternal scaffolding protein VP3 (Protein VP3) (VP3)
CAPSD_BPCHPCapsid protein VP1 (Protein VP1) (VP1)
H_BPCHPMinor spike protein H (H protein) (Pilot protein) (Protein VP2) (VP2)
J_BPCHPDNA binding protein ORF8
ORF6_BPCHPUncharacterized protein ORF6
ORF7_BPCHPUncharacterized protein ORF7
REP_BPCHPReplication-associated protein ORF4 (EC 3.1.21.-) (EC (Rep)

10 entries

Enterobacteria phage S13 (Bacteriophage S13)

Select_all Deselect_all  
G_BPS13Major spike protein G (G protein) (GPG)
SCAFB_BPS13Internal scaffolding protein B (Scaffolding protein B) (GPB)
SCAFD_BPS13External scaffolding protein D (Scaffolding protein D) (GPD)
VGA_BPS13A' protein (GPA)
VGC_BPS13C protein
VGE_BPS13Lysis protein (E protein) (GPE)
VGF_BPS13Capsid protein (F protein) (GPF)
VGH_BPS13Minor spike protein (H protein) (Pilot protein)
VGJ_BPS13Small core protein (J protein)
VGK_BPS13K protein

10 entries

Enterobacteria phage phiK (Bacteriophage phi-K)

Select_all Deselect_all  
G_BPPHKMajor spike protein G (G protein) (GPG)
SCAFB_BPPHKInternal scaffolding protein B (Scaffolding protein B) (GPB)
SCAFD_BPPHKExternal scaffolding protein D (Scaffolding protein D) (GPD)
VGA_BPPHKA protein (GPA)
VGC_BPPHKC protein
VGE_BPPHKLysis protein (E protein) (GPE)
VGF_BPPHKCapsid protein (F protein) (GPF)
VGH_BPPHKMinor spike protein (H protein) (Pilot protein)
VGJ_BPPHKSmall core protein (J protein)
VGK_BPPHKK protein