Asymmetrical Distribution of NeisseriaMiniature Insertion Sequence DNA Repeats among Pathogenic and Nonpathogenic NeisseriaStrains

ABSTRACTNeisseriaminiature insertion sequences (nemis) are miniature DNA insertion sequences found in Neisseriaspecies. Out of 57 elements closely flanking cellular genes analyzed by PCR, most were conserved in Neisseria meningitidisbut not in N. lactamicastrains. Since mRNAs spanning nemisare processed by RNase III at hairpins formed by element termini, gene sets could selectively be regulated in meningococci at the posttranscriptional level.