Viral contractile tail ejection system

The long and contractile tail of Myoviridae acts as a molecular machine that ejects the viral DNA from the capsid into the host cell cytoplasm. The ejection system consists of a baseplate, a central tube and an external contractile sheath .

Upon binding to the host cell surface, the baseplate changes its conformation and triggers sheath contraction, driving the rigid internal tail tube through the cell envelope.

The source of the forces that drive viral genome ejection is probably in part due to osmotic pressure imbalance between the virus inside and the host cytoplasm .

Gram(-) hosts:

image

  1. Attachment to a host cell outer membrane (OM) receptor.
  2. Tail sheath contraction. Ejection of the internal rigid tube through the OM using the puncturing device.
  3. Virion-associated exolysin (if present) hydrolyzes the peptidoglycan layer. Ejection of the internal rigid tube through the cell wall.
  4. Complete contraction and ejection of the internal rigid tube. Fusion with the inner membrane.
  5. Viral DNA translocation into host cytoplasm.

Gram(+) hosts:

image

  1. Attachment to a host cell wall receptor.
  2. Tail sheath contraction. Virion-associated exolysin (if present) hydrolyzes the peptidoglycan layer. Ejection of the internal rigid tube through the cell wall.
  3. Complete contraction and ejection of the internal rigid tube. Possible ejection of the tape-measure protein and opening of the proximal plug. Fusion with the plasma membrane.
  4. Viral DNA translocation into host cytoplasm.

Matching UniProtKB/Swiss-Prot entries

30 entries grouped by strain (browse by keywords)

5 entries

Escherichia phage Mu (Bacteriophage Mu) reference strain

Select_allDeselect_all
TUBE_BPMU Tail tube protein (TTP) (Gene product 40) (gp40) (Gene product M) (gpM)
PORTL_BPMU Portal protein (Gene product 29) (gp29) (Gene product H) (gpH) (Head-tail connector)
BP45_BPMU Baseplate puncturing device gp45 (Baseplate spike protein) (Gene product 45) (gp45) (Gene product Q) ...
BP44_BPMU Baseplate hub protein gp44 (43 kDa tail protein) (Gene product 44) (gp44) (Gene product P) (gpP)
TSP_BPMU Tail sheath protein (TSP) (Gene product 39) (gp39) (Gene product L) (gpL)

3 entries

Enterobacteria phage T4 (Bacteriophage T4) reference strain

Select_allDeselect_all
TUBE_BPT4 Tail tube protein gp19 (Gene product 19) (gp19)
TSP_BPT4 Tail sheath protein (TSP) (Gene product 18) (gp18)
PORTL_BPT4 Portal protein (Gene product 20) (gp20)

3 entries

Escherichia phage P2 (Bacteriophage P2) reference strain

Select_allDeselect_all
PORTL_BPP2 Probable portal protein (GpQ)
TSP_BPP2 Tail sheath protein (TSP) (Major tail sheath protein) (Protein FI)
TUBE_BPP2 Tail tube protein (TTP) (Protein FII)

2 entries

Bacillus phage SP01 (Bacteriophage SP01) reference strain

Select_allDeselect_all
TSP_BPSP1 Tail sheath protein (TSP)
PORTL_BPSP1 Probable portal protein

2 entries

Clostridium phage phiCD119 (strain Clostridium difficile/United States/Govind/2006) (Bacteriophage phiCD119) reference strain

Select_allDeselect_all
TSP_BPPCD Tail sheath protein (TSP)
PORTL_BPPCD Portal protein (Portal vertex protein)

2 entries

Salmonella phage ViI reference strain

Select_allDeselect_all
PORTL_BPSAV Portal protein (gp20)
TSP_BPSAV Tail sheath protein (TSP)

2 entries

Staphylococcus phage Twort (strain DSM 17442 / HER 48) (Bacteriophage Twort) reference strain

Select_allDeselect_all
TSP_BPTWO Tail sheath protein (TSP)
PORTL_BPTWO Probable portal protein

2 entries

Vibrio phage KVP40 (isolate Vibrio parahaemolyticus/Japan/Matsuzaki/1991) (KVP40) (Bacteriophage KVP40) reference strain

Select_allDeselect_all
PORTL_BPKVM Portal protein (gp20)
TSP_BPKVM Tail sheath protein (TSP)

1 entry

Burkholderia phage BcepMu (isolate -/United States/Summer/2002) (Bacteriophage BcepMu) reference strain

TSP_BPBMU Tail sheath protein (TSP)

1 entry

Enterococcus phage phiEF24C (Enterococcus bacteriophage phi-EF24C) reference strain

PORTL_BPPHE Probable portal protein

1 entry

Haemophilus phage HP1 (strain HP1c1) (Bacteriophage HP1) reference strain

PORTL_BPHC1 Probable portal protein (ORF15)

1 entry

Halomonas phage phiHAP-1 (isolate -/Gulf of Mexico/-/2001) (Bacteriophage phiHAP-1) reference strain

PORTL_BPHA1 Probable portal protein

1 entry

Mycobacterium phage Bxz1 (Mycobacteriophage Bxz1) reference strain

TSP_BPMBZ Tail sheath protein (TSP) (Gene product 124) (gp124)

2 entries

Serratia phage KSP20 (Serratia marcescens bacteriophage KSP20)

Select_allDeselect_all
TSP_BPSK2 Major tail sheath protein (Virion protein A)
TAILC_BPSK2 Major tail tube protein (GpFII-like protein) (Virion protein C)

1 entry

Enterobacteria phage T6 (Bacteriophage T6)

TUBE_BPT6 Tail tube protein gp19 (Gene product 19) (gp19)

1 entry

Serratia phage KSP90 (Serratia marcescens bacteriophage KSP90)

TUBE_BPSK9 Tail tube protein (Virion protein F)