Levivirus

VIRION

Non-enveloped, spherical virion about 26 nm in diameter with T=3 icosahedral symmetry composed of 178 CP proteins and a single A maturation protein .

GENOME

Monopartite, linear, ssRNA(+) genome about 3.5 kb in size. The 5' end is capped. Encodes 4 proteins.

GENE EXPRESSION

The virion RNA is infectious and serves as both the genome and viral messenger RNA. Encodes for 4 ORFs. Cp protein repress replicase translation by binding a RNA hairpin at the start site of this gene.

REPLICATION

  1. Adsorption to F pili of target cells induces cleavage and release of A maturation protein.
  2. Genomic RNA enters the bacterium.
  3. Viral proteins are translated.
  4. Viral replicase assembles with host proteins (ribosomal protein S1, translation elongation factors EF-Tu and EF-Ts) to form the active RNA polymerase.
  5. Replication of genomic RNA into a minus strand, which serves as template to produce new positive strand genomes.
  6. Late in infection CP protein bind to a RNA hairpin on the genome, and new virus particles are assembled in the cytoplasm.
  7. Release by cell lysis.

Matching UniProtKB/Swiss-Prot entries

18 entries grouped by strain (browse by keywords)

All proteins are shown (view only 12 complete proteome entries)

4 entries

Enterobacteria phage GA (Bacteriophage GA) reference strain

Select_allDeselect_all
CAPSD_BPGA Capsid protein (CP) (Coat protein)
MATA_BPGA Maturation protein A (MP) (Assembly protein) (A protein)
LYS_BPGA Lysis protein
RDRP_BPGA RNA-directed RNA polymerase beta chain (EC 2.7.7.48) (RNA replicase beta chain)

4 entries

Escherichia phage MS2 (Bacteriophage MS2) reference strain

Select_allDeselect_all
CAPSD_BPMS2 Capsid protein (CP) (Coat protein)
MATA_BPMS2 Maturation protein A (MP) (Assembly protein) (A protein)
LYS_BPMS2 Lysis protein (L protein)
RDRP_BPMS2 RNA-directed RNA polymerase beta chain (EC 2.7.7.48) (RNA replicase beta chain)

4 entries

Enterobacteria phage fr (Bacteriophage fr)

Select_allDeselect_all
CAPSD_BPFR Capsid protein (CP) (Coat protein)
LYS_BPFR Lysis protein
MATA_BPFR Maturation protein A (MP) (Assembly protein) (A protein)
RDRP_BPFR RNA-directed RNA polymerase beta chain (EC 2.7.7.48) (RNA replicase beta chain)

2 entries

Enterobacteria phage JP34 (Bacteriophage JP34)

Select_allDeselect_all
CAPSD_BPJP3 Capsid protein (CP) (Coat protein)
LYS_BPJP3 Lysis protein

1 entry

Enterobacteria phage R17 (Bacteriophage R17)

CAPSD_BPR17 Capsid protein (CP) (Coat protein)

1 entry

Enterobacteria phage ZR (Bacteriophage ZR)

CAPSD_BPZR Capsid protein (CP) (Coat protein)

1 entry

Enterobacteria phage f2 (Bacteriophage f2)

CAPSD_BPF2 Capsid protein (CP) (Coat protein)

1 entry

Pseudomonas phage PP7 (Bacteriophage PP7)

COAT_BPPP7 Coat protein