DNA sequence of the mini-insertion IS2--6 and its relation to the sequence of IS2

In polar IS2 abolishes galactose operon expression. Operon activity is restored by a 108 base pair mini-insertion within IS2 called IS2--6. The DNA sequences of the gal operon-IS2 junction, the parental IS2 region undergoing sequence rearrangements and IS2--6 itself are reported. IS2--6 is composed of sequence intervals present in both strands of IS2.