Jonas K, Tomenius H, Römling U, Georgellis D, Melefors O
FEMS Microbiol. Lett. 264 (2) 232-237 [2006-11-00; online 2006-10-27]
The Escherichia coli BarA-UvrY two-component system, which controls adaptation via the CsrB and CsrC sRNAs, is induced at the entry of the stationary phase by an unknown stimulus. Using a csrB-lacZ fusion, we demonstrated that the factors RelA, SpoT and LuxS, previously suggested to act on orthologues of this system, have no role in BarA-UvrY induction. However, using a transposon screen, we identified the hypothetical protein YhdA as a new regulator of CsrB and CsrC expression. The YhdA protein is predicted to be membrane-bound and to harbor GGDEF and EAL domains, which, however, are highly divergent from the consensus motifs.