title: Characterization and persistence of actinophage RP2 isolated from Streptomyces rimosus ATCC 10970.
abstract: While searching for true lysogens among oxytetracycline-producing Streptomyces rimosus strains, free phage particles were detected and isolated from a liquid culture of S. rimosus ATCC 10970 (R7). The actinophage, designated RP2, appears to be a typical temperate DNA phage producing turbid plaques on the sensitive strain S. rimosus R6. Electron microscopic examination of RP2 lysates showed that it belongs to group B of Bradley's morphological classification. The rate of RP2 adsoprption at 28 degrees C appeared to be low. The length of the latent period was about 6 h and the average burst size about 120 phage particles. The lysogenic nature of the host-virus system described was established on the basis of the following characteristics: spontaneous lysis frequency of 2 X 10(-6) per cell, resistance to curing with phage-specific antiserum, spontaneous curing frequency of less than 0.05% and immunity to superinfection with the homologous phage. Clear-plaque mutants of RP2, which failed to lysogenize sensitive cultures, arose at a frequency of 10(-5).
mesh_terms: D000327:Adsorption; D001435:Bacteriophages / Q000254:growth & development / Q000302:isolation & purification* / Q000648:ultrastructure; D004279:DNA, Viral / Q000032:analysis; D008242:Lysogeny; D009154:Mutation; D010118:Oxytetracycline / Q000096:biosynthesis; D013045:Species Specificity; D013302:Streptomyces / Q000378:metabolism; D014779:Virus Replication
chemical_list: D004279:DNA, Viral; D010118:Oxytetracycline