FIG. 6.

Target site requirements for IS492 excision. (A) Schematic diagram showing the extent of eps target sequence on either side of IS492 (left flanking sequence, open box; right flanking sequence, hatched box). The number at either end of IS492 indicates the number of nucleotides of eps sequence. Whether a circle junction PCR product could be detected is indicated as + or −. (B) Agarose gel electrophoresis of circle junction (CJ primers) PCR products and bla (bla primers) control products generated from plasmids carrying IS492 sequence with the flanking sequences shown in panel A. Lane M, Promega 1-kb marker, with the sizes of some of the markers (in base pairs) shown to the left.