title: Sensitivity of Escherichia coli to viral nucleic acid, X. Ba2+-induced competence for transfecting DNA.
abstract: Effect of alkaline earth metal ions on induction of the competence for DNA transfection was investigated. Unlike spheroplasts, the bulk of the bacteria treated with these ions retains colony-forming ability. The order of effectiveness for transfection of phiA replicative-form DNA has been found to be Ba2+ greater than Ca2+ greater than Sr2+ greater than Mg2+. The competence of Ba2+-treated cells is 3 to 5 times higher that that of Ca2+-treated bacteria and about 40 times higher than that of lysozyme-EDTA spheroplasts. The Ba2+-dependent transfection is cryophilic and formation of the infective complex occurs very rapidly at 0 degrees C, But not at 37 degrees C.
mesh_terms: D001464:Barium / Q000494:pharmacology*; D002118:Calcium / Q000494:pharmacology; D004279:DNA, Viral / Q000378:metabolism*; D004305:Dose-Response Relationship, Drug; D004926:Escherichia coli; D008274:Magnesium / Q000494:pharmacology; D013324:Strontium / Q000494:pharmacology; D013696:Temperature; D013997:Time Factors; D014170:Transformation, Genetic / Q000187:drug effects*
chemical_list: D004279:DNA, Viral; D001464:Barium; D008274:Magnesium; D002118:Calcium; D013324:Strontium