Microviridae

VIRION

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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.


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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. 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

78 entries grouped by strain (browse by keywords)

11 entries

Bdellovibrio phage phiMH2K (Bacteriophage phiMH2K) reference strain

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

10 entries

Enterobacteria phage S13 (Bacteriophage S13) reference strain

Select_allDeselect_all
SCAFD_BPS13 External scaffolding protein D (Scaffolding protein D) (GPD)
SCAFB_BPS13 Internal scaffolding protein B (EC 3.4.-.-) (Scaffolding protein B) (GPB)
VGJ_BPS13 Small core protein (J protein)
CAPSD_BPS13 Capsid protein F (F protein) (GPF)
G_BPS13 Major spike protein G (G protein) (GPG)
LYS_BPS13 Lysis protein (E protein) (GPE)
VGK_BPS13 K protein
VGA_BPS13 A' protein (GPA)
VGH_BPS13 Minor spike protein (H protein) (Pilot protein)
VGC_BPS13 C protein

10 entries

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

Select_allDeselect_all
SCAFD_BPPHS External scaffolding protein D (Scaffolding protein D) (GPD)
G_BPPHS Major spike protein G (G protein) (GPG)
REPA_BPPHS Replication-associated protein A (EC 3.1.21.-) (EC 6.5.1.1) (RepA)
SCAFB_BPPHS Internal scaffolding protein B (EC 3.4.-.-) (Scaffolding protein B) (GPB)
C_BPPHS Protein C
CAPSD_BPPHS Capsid protein F (F protein) (GPF)
LYS_BPPHS Lysis protein E (Protein E) (GPE)
H_BPPHS Minor spike protein H (H protein) (Pilot protein)
K_BPPHS Protein K
J_BPPHS DNA-binding protein J (J protein) (Small core protein)

10 entries

Escherichia phage G4 (Bacteriophage G4) reference strain

Select_allDeselect_all
SCAFB_BPG4 Internal scaffolding protein B (EC 3.4.-.-) (Scaffolding protein B) (GPB)
VGA_BPG4 A protein (GPA)
VGE_BPG4 Lysis protein (E protein) (GPE)
SCAFD_BPG4 External scaffolding protein D (Scaffolding protein D) (GPD)
CAPSD_BPG4 Capsid protein F (F protein) (GPF)
J_BPG4 DNA-binding protein J (J protein) (Small core protein)
G_BPG4 Major spike protein G (G protein) (GPG)
VGK_BPG4 K protein
VGC_BPG4 C protein
VGH_BPG4 Minor spike protein (H protein) (Pilot protein)

10 entries

Escherichia phage alpha3 (Bacteriophage alpha-3) reference strain

Select_allDeselect_all
VGK_BPAL3 K protein
VGE_BPAL3 Lysis protein (E protein) (GPE)
SCAFD_BPAL3 External scaffolding protein D (Scaffolding protein D) (GPD)
G_BPAL3 Major spike protein G (G protein) (GPG)
SCAFB_BPAL3 Internal scaffolding protein B (EC 3.4.-.-) (Scaffolding protein B) (GPB)
CAPSD_BPAL3 Capsid protein F (F protein) (GPF)
J_BPAL3 DNA-binding protein J (J protein) (Small core protein)
VGH_BPAL3 Minor spike protein (H protein) (Pilot protein)
VGA_BPAL3 A protein (GPA)
VGC_BPAL3 C protein

9 entries

Spiroplasma virus 4 (SpV4) reference strain

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

8 entries

Chlamydia phage 1 (Bacteriophage Chp1) reference strain

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

10 entries

Enterobacteria phage phiK (Bacteriophage phi-K)

Select_allDeselect_all
VGA_BPPHK A protein (GPA)
VGC_BPPHK C protein
SCAFD_BPPHK External scaffolding protein D (Scaffolding protein D) (GPD)
SCAFB_BPPHK Internal scaffolding protein B (EC 3.4.-.-) (Scaffolding protein B) (GPB)
CAPSD_BPPHK Capsid protein F (F protein) (GPF)
G_BPPHK Major spike protein G (G protein) (GPG)
J_BPPHK DNA-binding protein J (J protein) (Small core protein)
VGH_BPPHK Minor spike protein (H protein) (Pilot protein)
VGE_BPPHK Lysis protein (E protein) (GPE)
VGK_BPPHK K protein