- T7 phage
Bacteriophage T7 is a
phage capable of infecting susceptiblebacteria l cells. It infects most strains of "Escherichia coli " (including "", a strain of "E. coli" which can causefoodborne illness ).The virus is said to have complex structural symmetry, with a
capsid of the phage that isspherical with an inner diameter of 55 nm and a tail 19 nm in diameter and 28.5 nm long attached to the capsid. The head of the phage particle contains the roughly 40kbp dsDNA genome of T7.T7 has been used as a model in
synthetic biology . Chan et al 2005 [ [http://www.nature.com/msb/journal/v1/n1/full/msb4100025.html Molecular Systems Biology ] ] "refactored " the genome of T7, replacing approximately 12kbp of its genome with engineered DNA. The engineered DNA was designed to be easier to work with in a number of ways: individual functional elements were separated byrestriction endonuclease sites for simple modification, and overlapping protein coding domains were separated and, where necessary, modified by single base pairsilent mutations .Components
Gp5 (encoded by gene "gp5") is
T7 phage 'sDNA polymerase . T7 polymerase usesE. coli 's endogenousthioredoxin as asliding clamp during phageDNA replication (though thioredoxin normally has a different function). (The sliding clamp functions to hold the polymerase onto the DNA, which increases the rate of synthesis; initiation, the process by which a polymerase binds to DNA, is time-consuming.)References
* http://www.evergreen.edu/phage/docs/TOC_Forward.pdf
External links
*
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