An IS element, termed IS
Cg2, was identified in the chromosome of
Corynebacterium glutamicum ATCC 13032. After screening a cosmid library of the
C. glutamicum ATCC 13032 genome, six copies of IS
Cg2 including their flanking regions were sequenced and analyzed. IS
Cg2 is 1636 bp in length and has 26-bp imperfect inverted repeats flanked by 3-bp direct repeats. By comparisons with other IS
elements, IS
Cg2 was classified as a member of the IS
30 family of insertion sequences. The six copies of IS
Cg2 were identical at the nucleotide level and were located in intergenic, AT-rich regions of the chromosome. The regions in
which the six copies of IS
Cg2 were inserted displayed significant similarities. This similarity extends over a region of 65 bp, which was assumed to be
the target region for IS
Cg2. Interestingly, five of the six copies of IS
Cg2 were located adjacent to genes that may be involved in aspartate and glutamate metabolism or its regulation. Investigation
of the distribution of IS
Cg2 showed that the IS element is restricted to certain
C. glutamicum strains. Analysis of various integration regions indicates active transposition of IS
Cg2 in
C. glutamicum.
Received: 7 April 1999 / Accepted: 17 June 1999
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