FIG. 1.
(A) Genetic structures containing blaVEB genes and repeat elements. The species and isolate names are shown on the left. Insertion sequences are shown as pointed boxes labeled with the insertion sequence number, and Re1, Re2, and Re3 and their orientations are indicated. Gene cassettes are shown as open boxes, with small, filled boxes representing their attC sites. The extents of other resistance genes are shown, and the 5′-CS and 3′-CS of class 1 integrons and transposon fragments are labeled. Selected PCR products used for mapping are indicated by lines labeled with the primers used to amplify them. The region marked with an asterisk represents the first 1 to 111/114 bp of the 3′-CS. The structures for P. aeruginosa strains TL-1 and 10. 2 were drawn from sequences available under GenBank accession no. DQ315788 and AY444815, respectively, and P. stuartii B1 was drawn from the work of Aubert et al. (3). No additional information about flanking regions is available for 10.2 or B1. (B) Structure of Tn1331 and model for creation of a circular cassette containing aacA4 fused to the start of the blaTEM-1a gene. Circular molecules are not shown to scale. Tn1331 was drawn from the sequence available under GenBank accession no. AF479774.