The antiactivator FleN uses an allosteric mechanism to regulate σ⁵⁴-dependent expression of flagellar genes in Pseudomonas aeruginosa.

ABSTRACT: Diverse sigma factors associate with the RNA polymerase (RNAP) core enzyme to initiate transcription of specific target genes in bacteria. σ⁵⁴-Mediated transcription uses AAA+ activators that utilize their ATPase activity for transcription initiation. FleQ is a σ⁵⁴-dependent master transcriptional regulator of flagellar genes in Pseudomonas aeruginosa. The ATPase activity of FleQ is regulated via a P-loop ATPase, FleN, through protein-protein interaction. We report a high-resolution crystal structure of the AAA+ domain of FleQ in complex with antiactivator FleN. The data reveal that FleN allosterically prevents ATP binding to FleQ. Furthermore, FleN remodels the region of FleQ essential for engagement with σ⁵⁴ for transcription initiation. Disruption

SUBMITTER: Chanchal 

PROVIDER: S-EPMC8528422 | biostudies-literature | 2021 Oct

REPOSITORIES: biostudies-literature