Schematic representation of the sequences surrounding the blaTLA-1 gene in E. coli X170. The positions of primers shown in Table 1 are indicated by arrows; primers 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, and 21 are primers TLA-1F, TLA-1R, TLA-1-5′-TR1, TLA-1-5′-TR2, TLA-1-5′-TR3, IS91-5′-TR1, IS91-5′-TR4, IS91-5′-TR5, IS91-5′-TR6, IS91-5′-TR7, TLA-1-3′-TR1, TLA-1-3′-TR4, TLA-1-3′-TR5, TLA-1-3′-TR6, IS91-3′-extR, TLA-1-3′extF, IS91-5′-extR, IS91-3′extF, ISCR20F, maturase F, and methyl R, respectively. Genes are shown by large arrows, and the transcription orientations of the genes are indicated. The putative origin of replication, oriIS, and termination of transposition, terIS, of the ISCR20 element are indicated by a solid black circle and a black hairpin, respectively.