Fate of transforming DNA following uptake by competent Bacillus subtilis

Summary During transformation in Bacillus subtilis, donor and recipient DNA are initially associated by non-covalent bonds. The donor and recipient moieties later become covalently joined. The molecular weight of the donor component, when freed from the noncovalent complex by sucrose gradient sedimentation under alkaline conditions, ranges from 1 to 5×10⁶, with an average of about 2.5 to 3.0×10⁶. The latter values are in good agreement with previous measurements of the size of the integrated donor fragment.