TRANSPOSITION OF IST2 IN THIOBACILLUS-FERROOXIDANS

The genome of Thiobacillus ferrooxidans contains at least two differen t repetitive DNA elements. One of these elements, termed IST2 has been sequenced and shown to exhibit the characteristics of a typical proka ryotic insertion sequence. Furthermore, preliminary evidence has impli cated IST2 in genomic rearrangements, although the mechanism of rearra ngement, whether by transposition or recombination, has not been estab lished. In this report we provide evidence from detailed restriction e nzyme analyses and DNA sequencing data that support a model of transpo sition, consistent with the notion that IST2 is a mobile insertion seq uence.