Amino-terminal sequences of sigmaN (sigma54) inhibit RNA polymerase isomerization. Binding of transcriptional activators to sigma 54 in the presence of the transition state analog ADP-aluminum fluoride: insights into activator mechanochemical action. Design principles of the proteolytic cascade governing the sigmaE-mediated envelope stress response in Escherichia coli: keys to graded, buffered, and rapid signal transduction. Induction of the Escherichia coli aidB gene under oxygen-limiting conditions requires a functional rpoS (katF) gene. M. tuberculosis Ser/Thr protein kinase D phosphorylates an anti-anti-sigma factor homolog.

Probing the assembly of transcription initiation complexes through changes in sigmaN protease sensitivity. Proteotoxic stress induces a cell-cycle arrest by stimulating Lon to degrade the replication initiator DnaA. Region I modifies DNA-binding domain conformation of sigma 54 within the holoenzyme. Systematic analysis of sigma54 N-terminal sequences identifies regions involved in positive and negative regulation of transcription. The Rip1 intramembrane protease contributes to iron and zinc homeostasis in Mycobacterium tuberculosis.