FIG. 1.

ORF organization of arsI-containing regions in pSYSM and pSYSX. (A) Schematic representation of the pSYSM and pSYSX regions containing arsI. The repeated sequence is shaded. Arrows indicate the direction of transcription. Filled arrows represent antibiotic resistance cassettes, although for simplicity, only SpΩ is shown. (B) Schematic representation of the pSYSX ΔarsI region present in strains SARSI8, SARSI9, SARSI11, and SARS12. (C) Southern blot analysis of strains SARS4, SARS6, SARS7, SARS8, SARS9, SARS10, SARS11, and SARS12. Genomic DNA was digested with NcoI and hybridized using the same DNA fragment indicated in panel A as a probe. The sizes of the hybridizing bands are given on the right of the gels.