FIG. 1.

Organization of the antibiotic resistance gene cluster in SXT^MO10. The SXT^MO10 genes mediating resistance to antibiotics, dfr18, floR, strA, strB, and sulII, are represented by gray arrows, and genes with similarity to transposases (orf1, orf2, and orfA) are represented by hatched arrows. Genes encoding hypothetical proteins similar to known proteins are shown as horizontal hatches, and genes encoding hypothetical proteins dissimilar to known proteins are shown in white. Genes rumA and rumB are in black. The rumAB operon of R391 is presented above the SXT^MO10 antibiotic resistance gene region. The sequence in rumB which is repeated in SXT^MO10 is in bold and underlined; the flanking imperfect repeat (IR) sequences in SXT^MO10 are marked by arrows. Also indicated are the EcoRI sites (E) used for construction of pATMP1 and pSUL1. Regions of nucleotide sequence identity to other published nucleotide sequences are represented by boxes.