Characterization of bacteriophage phi C69 of Saccharopolyspora erythraea and demonstration of heterologous actinophage propagation by transfection of Streptomyces and Saccharopolyspora.

A bacteriophage, designated phi C69, isolated from a culture of Saccharopolyspora erythraea was characterized. The phage propagates on Sac. erythraea NRRL 2338 but does not infect 10 Streptomyces or 3 Micromonospora species tested. It infects Sac. erythraea NRRL 2359 but does not produce infectious phage particles in this host. phi C69 is approximately 40 kb in length and contains cohesive ends. A cos fragment containing ligated phage DNA ends was cloned in Escherichia coli. Restriction maps of the phage DNA and the cos fragment for several enzymes are shown. Transfection of both Sac. erythraea and Streptomyces lividans with phi C69 resulted in approximately equal titres of infectious phage particles produced from approximately the same number of regenerating cells. Transfection of Sac. erythraea with DNA from Streptomyces phages SH10 and KC404 also resulted in the production of infectious phage particles. The basis for differences among hosts in susceptibility to infection by various actinophages is discussed.