PG1659 functions as anti‐sigma factor to extracytoplasmic function sigma factor RpoE in Porphyromonas gingivalis W83. (13th January 2021)

• Record Type: Journal Article
• Authors: Dou, Yuetan; Rutanhira, Hiel; Schormann, Norbert; Deivanayagam, Champion; Fletcher, Hansel M.
• Is Part Of: Molecular oral microbiology. Volume 36:Number 1(2021)
• Page Start: 80
• Page End: 91
• Publication Date: 2021-01-13
• Subjects: anti‐sigma factor -- oxidative stress -- Porphyromonas gingivalis -- sigma factor; Mouth -- Microbiology -- Periodicals; Respiratory infections -- Microbiology -- Periodicals; Mouth -- Diseases -- Immunological aspects -- Periodicals; 617.522
• DOI: 10.1111/omi.12329
• Languages: English
• ISSNs: 2041-1006

Abstract

Abstract: Anti‐sigma factors play a critical role in regulating the expression of sigma factors in response to environmental stress signals. PG1659 is cotranscribed with an upstream gene PG1660 ( rpoE ), which encodes for a sigma factor that plays an important role in oxidative stress resistance and the virulence regulatory network of P . gingivalis . PG1659, which is annotated as a hypothetical gene, is evaluated in this study. PG1659, composed of 130 amino acids, is predicted to be transmembrane protein with a single calcium (Ca 2+ ) binding site. In P . gingivalis FLL358 (Δ PG1659 :: ermF ), the rpoE gene was highly upregulated compared to the wild‐type W83 strain. RpoE‐induced genes were also upregulated in the PG1659 ‐defective isogenic mutant. Both protein‐protein pull‐down and bacterial two‐hybrid assays revealed that the PG1659 protein could interact with/bind RpoE. The N‐terminal domain of PG1659, representing the cytoplasmic fragment of the protein, is critical for interaction with RpoE. In the presence of PG1659, the initiation of transcription by the RpoE sigma factor was inhibited. Taken together, our data suggest that PG1659 is an anti‐sigma factor which plays an important regulatory role in the modulation of the sigma factor RpoE in P . gingivalis . Abstract : The sigma factor RopE plays an important role in oxidative stress resistance and the virulence regulatory network in P. gingivalis . Collectively, the data in this report have demonstrated the functional properties of anti‐sigma factor PG1659 in its modulation of RopE in P. gingivalis . It is likely that PG1659 is involved in a complex regulatory network that may represent a yet‐to‐be described oxidative stress resistance pathway in P. gingivalis .