Mutational analysis of the cyanobacterial nitrogen regulator PipX.

ABSTRACT: PipX provides a functional link between the cyanobacterial global transcriptional regulator NtcA and the signal transduction protein P(II), a protein found in all three domains of life as integrators of signals of the nitrogen and carbon balance. PipX, which is toxic in the absence of P(II), can form alternative complexes with NtcA and P(II) and these interactions are respectively stimulated and inhibited by 2-oxoglutarate, providing a mechanism by which P(II) can modulate expression at the NtcA regulon. Structural information on PipX-NtcA complexes suggests that PipX coactivates NtcA controlled genes by stabilizing the active conformation of NtcA bound to 2-oxoglutarate and by possibly helping recruit RNA polymerase. To get insights into PipX functions, we perform here a mutational analys

SUBMITTER: Laichoubi KB 

PROVIDER: S-EPMC3340408 | biostudies-literature | 2012

REPOSITORIES: biostudies-literature