The fur-regulated gene encoding the alternative sigma factor PvdS is required for iron-dependent expression of the LysR-type regulator ptxR in Pseudomonas aeruginosa.

ABSTRACT: We previously identified a novel regulator of the exotoxin A gene (toxA) in Pseudomonas aeruginosa, PtxR, that belongs to the LysR family of prokaryotic regulatory proteins. Preliminary data also suggest that PtxR affects the expression of siderophores in P. aeruginosa. Because toxA expression and siderophore production in this organism are coordinately regulated by the ferric uptake regulator (Fur) and the Fur-regulated alternative sigma factor PvdS, regulation of ptxR itself in the context of these regulators was examined. RNase protection analyses of ptxR transcription revealed that there are two independent transcription initiation sites (T1 and T2). While transcription from the promoter of T1 is constitutive throughout the growth cycle of PAO1, transcription from the second promoter (

SUBMITTER: Vasil ML 

PROVIDER: S-EPMC107792 | biostudies-literature | 1998 Dec

REPOSITORIES: biostudies-literature