Escherichia virus G4 is a
bacteriophage
A bacteriophage (), also known informally as a ''phage'' (), is a duplodnaviria virus that infects and replicates within bacteria and archaea. The term was derived from "bacteria" and the Greek φαγεῖν ('), meaning "to devour". Bacteri ...
that infects ''
E. coli
''Escherichia coli'' (),Wells, J. C. (2000) Longman Pronunciation Dictionary. Harlow ngland Pearson Education Ltd. also known as ''E. coli'' (), is a Gram-negative, facultative anaerobic, rod-shaped, coliform bacterium of the genus ''Escher ...
''.
First isolated in 1973, the phage was originally isolated from samples of raw sewage and has 5,577 nucleotides. Its isometric
capsid contains a single-stranded circular
genome
In the fields of molecular biology and genetics, a genome is all the genetic information of an organism. It consists of nucleotide sequences of DNA (or RNA in RNA viruses). The nuclear genome includes protein-coding genes and non-coding ge ...
of about 5.5
kbp. Phage G4 bears high genetic and structural similarity to the phage
ΦX174
The phi X 174 (or ΦX174) bacteriophage is a single-stranded DNA ( ssDNA) virus that infects ''Escherichia coli'', and the first DNA-based genome to be sequenced. This work was completed by Fred Sanger and his team in 1977. In 1962, Walter Fie ...
, though the two phage genomes are up to 39 percent different by sequence.
Synthetic G4
Synthetic G4 (syn-G4) has the appearance of an icosahedral protein shell and is 50 nm in diameter. has been synthesized through
Polymerase Chain Reaction (PCR) assembly of short
oligonucleotides. The synthetic phage G4 genomes were effective in ''
E. coli
''Escherichia coli'' (),Wells, J. C. (2000) Longman Pronunciation Dictionary. Harlow ngland Pearson Education Ltd. also known as ''E. coli'' (), is a Gram-negative, facultative anaerobic, rod-shaped, coliform bacterium of the genus ''Escher ...
''.
Phage Therapy
Urinary Tract Infections (UTIs) are mainly caused by uropathogenic E. coli, and bacteriophage G4 can be used to treat it. The bacteriophage inject their DNA into the bacteria, releasing many new bacteriophages. This process has many benefits:
# The bacteriophage do not attack animal or human cells, only E. coli bacteria.
# The bacteriophage reproduce exponentially, so only a small amount is needed.
# After the bacteriophage have attached and killed all the bacteria, they disperse throughout the body and are harmless.
References
External links
UniProt TaxonomyNCBI TaxonomyNCBI Nucleotide (full genome)
{{Taxonbar, from=Q5380215
Microviridae