Protease-sensitive transfection of Bacillus subtilis with bacteriophage GA-1 DNA: a probable case of heterologous transfection.
The host bacterium of bacteriophage GA-1, Bacillus sp. G1R, was compared with respect to its taxonomic relationship to Bacillus subtilis, B. licheniformis, and B. pumilis. The physiological-biochemical properties of Bacillus sp. G1R are equal to those of B. licheniformis, but the thermal denaturation midpoint of G1R DNA differs by 3 C and the buoyant density by 0.005 g/cm(3) from that of B. licheniformis. Transformation with G1R donor DNA was neither observed in B. licheniformis nor in B. subtilis-competent recipients. Bacteriophage GA-1 shows neither infectivity on B. licheniformis nor on B. subtilis. However, infection of competent B. subtilis cultures with phenol-extracted GA-1 DNA results in the production of infective GA-1 particles. The transfecting activity of GA-1 DNA is destroyed by treatment with proteolytic enzymes. Resistance of transfecting DNA to inactivation by trypsin develops earlier than that to inactivation by DNase. Protease-treated GA-1 DNA competes with transforming DNA to approximately the same extent as does untreated GA-1 DNA, suggesting that uptake of GA-1 DNA is not affected by protease treatment. CsCl density gradient centrifugation reveals that the density of trypsinized GA-1 DNA is 0.004 g/cm(3) greater than that of untreated DNA.
D001407:Bacillus / Q000145:classification; D001412:Bacillus subtilis / Q000145:classification; D001435:Bacteriophages / Q000032:analysis*; D002499:Centrifugation, Density Gradient; D003596:Cytosine / Q000032:analysis; D004269:DNA, Bacterial / Q000032:analysis; D004279:DNA, Viral / Q000032:analysis*; D006147:Guanine / Q000032:analysis; D008242:Lysogeny; D008970:Molecular Weight; D010447:Peptide Hydrolases / Q000494:pharmacology; D014170:Transformation, Genetic; D014357:Trypsin / Q000494:pharmacology
D004269:DNA, Bacterial; D004279:DNA, Viral; D006147:Guanine; D003596:Cytosine; D010447:Peptide Hydrolases; D014357:Trypsin