Microviridae

VIRION

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.


GENOME

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

GENE EXPRESSION

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

REPLICATION

CYTOPLASMIC

  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_allDeselect_all
W_BPPHM Uncharacterized protein W
X_BPPHM Uncharacterized protein X
Y_BPPHM Uncharacterized protein Y
Z_BPPHM Uncharacterized protein Z
B_BPPHM Internal scaffolding protein VP3
CAPSD_BPPHM Capsid protein VP1 (VP1)
C_BPPHM Protein VP5
H_BPPHM Minor spike protein H (H protein) (Pilot protein) (Protein VP2) (VP2)
N_BPPHM Uncharacterized protein N
J_BPPHM DNA binding protein VP8
REP_BPPHM Replication-associated protein VP4 (Rep) (VP4) (EC 3.1.21.-) (EC 6.5.1.1)

10 entries

Enterobacteria phage alpha3 (Bacteriophage alpha-3) reference strain

Select_allDeselect_all
VGA_BPAL3 A protein (GPA)
VGF_BPAL3 Capsid protein (F protein) (GPF)
VGH_BPAL3 Minor spike protein (H protein) (Pilot protein)
VGE_BPAL3 Lysis protein (E protein) (GPE)
VGC_BPAL3 C protein
VGK_BPAL3 K protein
G_BPAL3 Major spike protein G (G protein) (GPG)
J_BPAL3 DNA-binding protein J (J protein) (Small core protein)
SCAFB_BPAL3 Internal scaffolding protein B (Scaffolding protein B) (GPB)
SCAFD_BPAL3 External scaffolding protein D (Scaffolding protein D) (GPD)

10 entries

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

Select_allDeselect_all
CAPSD_BPPHS Capsid protein F (F protein) (GPF)
C_BPPHS Protein C
E_BPPHS Lysis protein E (Protein E) (GPE)
G_BPPHS Major spike protein G (G protein) (GPG)
H_BPPHS Minor spike protein H (H protein) (Pilot protein)
J_BPPHS DNA-binding protein J (J protein) (Small core protein)
K_BPPHS Protein K
REPA_BPPHS Replication-associated protein A (EC 3.1.21.-) (EC 6.5.1.1) (RepA)
SCAFB_BPPHS Internal scaffolding protein B (Scaffolding protein B) (GPB)
SCAFD_BPPHS External scaffolding protein D (Scaffolding protein D) (GPD)

9 entries

Spiroplasma virus 4 (SpV4) reference strain

Select_allDeselect_all
B_SPV4 Internal scaffolding protein ORF3
CAPSD_SPV4 Capsid protein VP1 (VP1)
C_SPV4 Protein ORF5
H_SPV4 Minor spike protein H (H protein) (Pilot protein)
ORF9_SPV4 Uncharacterized protein ORF9
ORF7_SPV4 Uncharacterized protein ORF7
ORF6_SPV4 Uncharacterized protein ORF6
J_SPV4 DNA binding protein ORF8
REP_SPV4 Replication-associated protein ORF2 (EC 3.1.21.-) (EC 6.5.1.1) (Rep)

8 entries

Chlamydia phage 1 (Bacteriophage Chp1) reference strain

Select_allDeselect_all
CAPSD_BPCHP Capsid protein VP1 (Protein VP1) (VP1)
B_BPCHP Internal scaffolding protein VP3 (Protein VP3) (VP3)
C_BPCHP Protein ORF5
H_BPCHP Minor spike protein H (H protein) (Pilot protein) (Protein VP2) (VP2)
ORF6_BPCHP Uncharacterized protein ORF6
ORF7_BPCHP Uncharacterized protein ORF7
J_BPCHP DNA binding protein ORF8
REP_BPCHP Replication-associated protein ORF4 (EC 3.1.21.-) (EC 6.5.1.1) (Rep)

10 entries

Enterobacteria phage G4 (Bacteriophage G4)

Select_allDeselect_all
VGC_BPG4 C protein
VGF_BPG4 Capsid protein (F protein) (GPF)
VGE_BPG4 Lysis protein (E protein) (GPE)
VGA_BPG4 A protein (GPA)
VGK_BPG4 K protein
VGH_BPG4 Minor spike protein (H protein) (Pilot protein)
G_BPG4 Major spike protein G (G protein) (GPG)
J_BPG4 DNA-binding protein J (J protein) (Small core protein)
SCAFB_BPG4 Internal scaffolding protein B (Scaffolding protein B) (GPB)
SCAFD_BPG4 External scaffolding protein D (Scaffolding protein D) (GPD)

10 entries

Enterobacteria phage S13 (Bacteriophage S13)

Select_allDeselect_all
VGA_BPS13 A' protein (GPA)
VGJ_BPS13 Small core protein (J protein)
VGH_BPS13 Minor spike protein (H protein) (Pilot protein)
VGC_BPS13 C protein
VGE_BPS13 Lysis protein (E protein) (GPE)
VGF_BPS13 Capsid protein (F protein) (GPF)
VGK_BPS13 K protein
G_BPS13 Major spike protein G (G protein) (GPG)
SCAFB_BPS13 Internal scaffolding protein B (Scaffolding protein B) (GPB)
SCAFD_BPS13 External scaffolding protein D (Scaffolding protein D) (GPD)

10 entries

Enterobacteria phage phiK (Bacteriophage phi-K)

Select_allDeselect_all
VGC_BPPHK C protein
VGF_BPPHK Capsid protein (F protein) (GPF)
VGH_BPPHK Minor spike protein (H protein) (Pilot protein)
VGA_BPPHK A protein (GPA)
VGK_BPPHK K protein
VGE_BPPHK Lysis protein (E protein) (GPE)
G_BPPHK Major spike protein G (G protein) (GPG)
J_BPPHK DNA-binding protein J (J protein) (Small core protein)
SCAFD_BPPHK External scaffolding protein D (Scaffolding protein D) (GPD)
SCAFB_BPPHK Internal scaffolding protein B (Scaffolding protein B) (GPB)