Viral receptor tropism switching

Some bacteriophages have developed tropism-switching genetic cassettes, that allow them to modify their fibers proteins, and thus to bind to a broader range of hosts.

Different mechanisms can be used:

  1. The host range variation system found in phages such as Mu and P1 is a genetic system that allows some bacterial viruses to switch between two types of fibers by inversion of the DNA segment encoding the fibers. The change in fibers specificity is performed through site specific inversion of a genome segment catalyzed by a virally encoded invertase. This genome segment codes for two alternate sets of tail fibers, of which only the "well oriented" one is expressed .
  2. Bordetella bacteriophages generate diversity in a gene that specifies host tropism produced through a genetic element that combines the basic retroelement life cycle of transcription, reverse transcription and integration with site-directed, adenine-specific mutagenesis .


Matching UniProtKB/Swiss-Prot entries

10 entries grouped by strain (browse by keywords)

5 entries

Escherichia phage Mu (Bacteriophage Mu) reference strain

U2_BPMU Tail fiber assembly protein U' (Gene product U') (gpU')
S2_BPMU Tail fiber protein S' (Gene product S') (gpS')
S1_BPMU Tail fiber protein S (Gene product 49) (gp49) (Gene product S) (gpS)
U1_BPMU Tail fiber assembly protein U (Gene product 50) (gp50) (Gene product U) (gpU)
GIN_BPMU Serine recombinase gin (EC 3.1.22.-) (EC 6.5.1.-) (G-segment invertase) (Gin) (Gene product 53) ...

3 entries

Escherichia phage P1 (Bacteriophage P1) reference strain

U1_BPP1 Tail fiber assembly protein U (Gene product U) (gpU)
U2_BPP1 Tail fiber assembly protein U' (Gene product U') (gpU')
CIN_BPP1 DNA-invertase (Site-specific recombinase)

1 entry

Bordetella phage BPP-1 reference strain

FIBD_BPBPP Tail fiber receptor-binding protein (Major tropism determinant protein)

1 entry

Enterobacteria phage P7 (Bacteriophage P7)

CIN_BPP7 DNA-invertase (Site-specific recombinase)