Figure 2.

Functional distribution of in vivo repressed (ivr) genes of V. cholerae. Shown are ivr genes identified with the TetR-controlled recombination-based screening technology, allocated in functional groups by their proposed function according to KEGG (http://www.genome.jp/kegg/). The number of ivr genes in the respective group is indicated in parenthesis. In case of TRIVET, the pTRIVET suicide vector harbouring a TetR-controlled tnpR allele is integrated next to the res cassette. The tpc cassette is mobilized into the chromosome via Tn10 mutagenesis resulting in transcriptional fusion and control by the chromosomal promotor of geneX. Loss of TetR expression via repression of the geneX promotor results in de-repression of tnpR and irreversible excision of the res cassette causing the same resistance profile as described above (Kn^R & Suc^S) to (Kn^S & Suc^R).