Preparation and Characterization of Temperate, Non-inducible Bacteriophage P2 (host: Escherichia coli)

Abstract
Summary P2 phage particles contained DNA (38%) and protein (62%), and were assigned a particle weight of 5.8 × 107 daltons, based on the known molecular weight of P2 DNA. The extinction (1 cm.) of suspensions of 1011 particles per ml. was 0.09 at 260 nm. wavelength. In purified preparations 20 to 50% of the particles present were not detected by biological assay. The preparations were heterogeneous in respect to heat stability. Even at relatively low temperatures, changes in light scattering accompanied heat inactivation.