title: Protease-sensitive transfection of Streptococcus pneumoniae with bacteriophage Cp-1 DNA.
abstract: The transfecting activity of pneumococcal phage Cp-1 DNA was destroyed by treatment with proteolytic enzymes, although these enzymes did not affect transfection with bacteriophage Dp-4 DNA. This transfection was stimulated by calcium ions. Protease-treated Cp-1 DNA competes for binding and uptake with transforming pneumococcal DNA as well as with transfecting Dp-4 DNA to approximately the same extent as does untreated Cp-1 DNA. In addition, [3H]thymidine-labeled Cp-1 DNA, treated with proteases or untreated, was absorbed with the same efficiency. These data suggest that uptake of Cp-1 DNA is not affected by protease treatment. [3H]thymidine-labeled Cp-1 DNA showed remarkable resistance against surface nuclease activity of competent wild-type cells. The monomeric form of the Cp-1 DNA-protein complex showed a linear dose response in transfection.
mesh_terms: D001435:Bacteriophages / Q000235:genetics*; D004279:DNA, Viral / Q000378:metabolism*; D009154:Mutation; D010447:Peptide Hydrolases / Q000378:metabolism*; D013296:Streptococcus pneumoniae / Q000235:genetics*; D014162:Transfection; D014170:Transformation, Genetic; D014764:Viral Proteins / Q000378:metabolism
chemical_list: D004279:DNA, Viral; D014764:Viral Proteins; D010447:Peptide Hydrolases