our increasing knowledge of the diversity of the mobilome, the distinction
between IS and other TE is becoming increasing unclear. The major feature used
to distinguish IS from transposons was that the former (Fig
phenotypically detectable passenger genes (genes not involved in the
transposition process) while the latter include one or more such genes (for
antibiotic resistance, virulence and pathogenicity functions or genes
permitting the use of unusual compounds). This is no longer the case. As shown
in Fig 1.13.1, examples have now been identified in which passenger genes are located within an IS, called tIS (ISs and relatives with passenger genes) or in which TE with typical transposon structures are devoid of
transposition proteins (MITES and MIC). The (hypothetical) relationship between
these different autonomous (with transposase) and non-autonomous IS derivatives
is indicated in Fig 1.13.1 (Siguier, et al., 2014).
- Siguier P, Gourbeyre E & Chandler
M (2014) Bacterial insertion sequences: their genomic impact and diversity. FEMS Microbiol Rev.