A schematic representing the four forms of the qrg gene and IS1216 insertion found in Tn6087. A) The entire 3124 bp insertion within orf15; B) the entire insertion excised from orf15; C) only a chimeric form of the two IS1216 sequences remaining; D) and a circular molecule consisting qrg, the hypothetical protein and the IS1216 1 sequence. The forms described were obtained by sequencing amplicons resulting from reactions using the primers shown in (A).