Table 1.

Bacterial strains and plasmids used in this work

Strain or plasmidRelevant characteristicsSource or reference
E. coli
 JM103 hsdR4Δ(lac-pro) F′ traD36 proAB lacI qZΔM153
 S17-1 recA endA thi hsdR RP4-2-Tc::Mu::Tn7; Tpr Smr 27
R. sphaeroides
 WS8Wild type; spontaneous Nalr 30
 LC1WS8flgE::aadA; SpcrNalr This work
 TE1WS8 TnphoAderivative, flgE::TnphoA; Kmr Nalr This work
Plasmids
 pTZ19RCloning vector; Apr; pUC derivativePharmacia
 pWM5Plasmid carrying the omega-Spc cassette17
 pJQ200mp18Suicide vector used for gene replacement in gram-negative bacteria24
 pRK415pRK404 derivative, used for expression in R. sphaeroides 13
 pU1800pSUP203 derivative carrying TnphoA; Cmr TcrKmr 19
 pRS20002.0-kb fragment carryingflgE and flgE obtained by PCR, cloned into pRK415This work
 pRS2001pRK415 carrying theflgEΔ1 alleleThis work
 pRS43004.3-kbPstI fragment from WS8 cloned into pTZ19RThis work
 pRS4303/43034.3-kb PstI fragment from pRS4300 subcloned into pRK415/reversed direction.This work
 pRS56005.6-kb SalI fragment cloned into pTZ19R containing 4.6-kb of TnphoA plus 1 kb of TE1 DNA flanking the site of transposon insertion; KmrApr This work