[Immunogenic DNA of Shigella sonnei bacteriophage]

Immunogenic and some other properties of Sh, sonnei "Ufa" phage DNA were investigated. This DNA has been shown to possess high immunogenic activity indicating the presence of an unusual base. The base is distinct from 5-OmC, glucosylated 5-OmC, 5-OmU or dihydroxypentyluracil. The phage DNA is double stranded and has the molecular weight of 1.11.10(8) daltons and Tm=85.5 degrees C. Base sequences common with T4 DNA have been found using the competition DNA-DNA hybridization technique. Experiments on cross neutralization of intact phage with the corresponding antisera confirm the existence of common antigenic determinants in T4 and Sh, sonnei "Ufa" phage particles.