Confirmation of tagging <i>C. botulinum</i> BoNT-encoding plasmids pBotCDC-A3-Erm (strain CDC-A3), pCLJ-Erm (strain 657Ba) and pCLL-Erm (strain Eklund 17B) by PFGE and Southern hybridization analysis.

<p>(<b>B</b>) Ethidium bromide stained PFGE of nondigested DNA samples from <i>C. botulinum</i> strains: wild type CDC-A3 (Lane 1), CDC-A3580s1 (Lane 2), wild type 657Ba (Lane 3), 657Ba-CT4 (Lane 4), wild type Eklund 17B (Lane 5) and Eklund17B-CT11 (Lane 6); Lambda PFG Marker (Lane M), (New England Biolabs). The position of BoNT-encoding plasmids is indicated with arrows. (<b>A</b>) Southern hybridization with the <i>bont/A3</i> probe (Lanes 1 and 2); the <i>bont/bvB</i> probe (Lanes 3 and 4) and the <i>bont/npB</i> probe (Lanes 5 and 6); (<b>C</b>) Southern hybridization with the <i>ermB</i> probe. PFGE conditions: 6V/cm, 12°C, 1–20 s pulse time, 24 h.