Summary
Phage-like particles from kappa of stock 562 of Paramecium aurelia have been isolated by CsCl density gradient centrifugation. Analyses show that the particles contain about 1.6×1016g DNA and 2.0×10-16g protein. Their buoyant density is approximately 1.47. DNA from the particles has a buoyant density very close to that of whole kappa DNA. The presence of DNA in the particles has been confirmed by a cytochemical technique. The results support the conclusion that kappa contains a bacteriophage.
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Communicated by Ch. Auerbach
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Preer, J.R., Preer, L.B., Rudman, B. et al. Isolation and composition of bacteriophage-like particles from kappa of killer paramecia. Molec. Gen. Genet. 111, 202–208 (1971). https://doi.org/10.1007/BF00433105
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DOI: https://doi.org/10.1007/BF00433105