Analysis of the pT181-based staphylococcal modules. Whole-cell sheared minilysates of S. aureus RN4220 strains containing the indicated plasmids were separated on 1% agarose in Tris-borate buffer for 18 h at 2.5 V/cm, stained with ethidium bromide, and photographed. Samples corresponding to equivalent numbers of cells were used to permit comparison. (A) Strains were grown at 32°C. Lane 1, RN4220; lane 2, RN2424; lane 3, RN4253; lane 4, RN4416; lane 5, RN9582, lane 6, RN9586; lane 7, RN9593. (B) Experiments were conducted at 43°C. Lane 1, RN4220; lane 2, RN9582; lane 3, RN9593. The heavy upper band corresponds to sheared chromosomal DNA. The supercoiled plasmid bands are indicated with arrows. Intermediate plasmid bands correspond to topoisomers and multimers.