UA Biophysics:Protocols:Marking T4 DNA with DAPI

WARNING

This protocol CAN'T be done at the installations of the biophysics laboratory as it compromises the safety of the biological samples present at it.

Purpose

Mark T4 DNA with 4’,6-diamidino-2-phenylindle (DAPI).

Recipe

For this procedure, a modified version of the methodology given by Furukawa et. al.[1] elaborated for a simple of 10^9 PFU/ μl will be used. E. coli B is cultured to 0.5 x 108 cells per ml in 25 ml of TSB 30 gr/l (OXOID). The phage is added ensuring a multiplicity of infection (MOI) of 5 particles per cell and, simultaneously, DAPI (4’,6-diamidino-2-phenylindle from SIGMA) is added to a concentration of 5 μg/ml. 6 hours later cloroform is added to 0.1%.

Other Links

• Fluorescence Ex/Em spectra of DAPI bound to DNA: [1]

References

[1] Furukawa, H., Kuroiwa, T. & Mizushima, S. DNA injection during bacteriophage T4 infection of Escherichia coli. J. Bacteriol. 154, 938–945 (1983).