Table 1.

Bacterial strains and plasmids used

Strain or plasmidaRelevant characteristic(s)bReference or source
E. coli
  S605 met::Tn5 W. Klipp, Bielefeld, Germany
  A118Chromosomally located Tn5lac 49
  DH5α hsdR17 endA1 thi-1 gyrA96 relA1 recA1 supE44 ΔlacU169(φ80dlacZΔM15)Gibco-BRL
S. meliloti
  2011Wild typec
  2011rhbA62 rhbA::Tn5lac, rif This study
  2011rhbC2 rhbC::Tn5mob, rif 46
  2011rhbE11 rhbE::Tn5lac, rif This study
  2011rhbE9 rhbE::Tn5, rif This study
  2011rhbF104 rhbF::Tn5lac, rif This study
  2011rhbF107 rhbF::Tn5lac, rif This study
  2011rhrA4 rhrA::Tn5lac, rif This study
  2011rhrA6 rhrA::Tn5, rif This study
  2011rhrA26 rhrA::Tn5lac, rif This study
  2011rhtA45 rhtA::Tn5lac, rif This study
  2011rhtA42 rhtA::Tn5lac, rif This study
  2011rhtA1 rhtA::Tn5, rif This study
  SmA818Cured of pSyma40
  SmA416BTWDeletion in pSyma40
 pJQ200ksGmr, mob sacB 45
 pGR30Cosmid carrying rhizobactin 1021 synthesis, regulation, and uptake genes, Tcr 46
 pRK600Tra+, Cmr 15
 pDL80pJQ200ks carrying 8.0-kb genomic BamHI insertThis study
 pUC18–52pUC18 carrying 5.2-kb genomicBamHI insertThis study
 pDL30pJQ200ks carrying 3.0-kb XhoI-BamHI fragment from pUC18–52This study
  • a pUC18-based constructs used for sequencing are not included.

  • b Apr, Cmr, Gmr, and Tcr, ampicillin, chloramphenicol, gentamicin, and tetracycline resistance, respectively; mob, mobilization; Tra+, transfer.

  • c S. meliloti 2011 is the parent strain of 1021 (35) from which rhizobactin 1021 was purified and chemically characterized (42). A rifampin-resistant derivative (rif) was used in the construction of transposon insertion mutants. To facilitate the use of the npt probe to compare relative abundance of RNA in Tn5lac-induced mutants and wild type, a derivative with a Tn5 insertion in a rhamnose utilization gene (provided by Michael Hynes, University of Calgary) was used instead of wild type.