FIG 1.

Schema of SGI1 variants. The chromosomal genes are in pink, the backbones of SGI1 variants are in blue, and the multiple-antibiotic-resistance (MAR) region and IS1359 are represented in yellow. attL and attR are the left and right attachment sites, respectively. The position of the class 1 integron is indicated by the 5-bp duplication (ACTTG). (A) SGI1 and SGI1-HKL variant group. SGI1 has already been reported to be inserted at the 3′-end of the trmE gene upstream of the following chromosomal (Chr) genes: the int2 gene (retron phage gene) in S. Typhimurium DT104, the yidY gene of S. enterica, and the hipB gene of Proteus mirabilis. The SGI1-H, -K, and -L groups were previously reported to be inserted at the 3′-end of the trmE gene upstream of the following chromosomal genes: the yidY gene in S. enterica, the hipB gene in P. mirabilis, and the permease gene in Morganella morganii. *, the 5′-end of S044 is deleted in SGI1-K variants. (B) SGI1-LK1 variant. The SGI1-LK1 variant is inserted at the 3′-end of the trmE gene upstream of the hipB gene of P. mirabilis.