E.coli NrdR Expression and LC-MSMS

ABSTRACT: Transcription factors regulate the geneexpression for ordered cellular metabolism, and its change implicated to virulence in several bacterial pathogens including E. coli causing gastroenteritis and colon cancer. Novel transcription regulator NrdR known for regulating ribonucleotide reductase (RNRs) expression for dNTP synthesis is recently implicated to bacterial chemotaxis and cell adhesion. However, NrdR deletion shows no effect on the bacterial growth or virulence in infected flies, and the corresponding transcriptiomic studies indicate to upregulation of RNRs alone. However, this data limited only to the deletion strain and inadequate to draw biological implications when the repressor is active. Here, we have performed a comprehensive proteomic analysis of both deletion and overexpression of NrdR. In addition, we have profiled the bacterial fate with the aid of biochemical assays and at physiological level. Our results demonstrate that increased NrdR expression brings a significant change in bacterial morphology, has fitness defect and cannot withstand stress conditions. The fitness defect in stress condition can be attributed to the depletion of proteins in cellular integrity pathway detected from proteome analysis, which is also evidenced by deprived bacterial cell. This also has a negative consequence on its efficiency in colonizing to human epithelial cells. Further corroborating these as direct effects NrdR overexpression causes a significant decrease in global protein expression, primarily in proteins belonging to carbohydrate and amino acid metabolic pathways. Our results increases the understanding on how bacterial cells can infiltrate and colonize in host cells and can thus caters to the broad interest of bacteriologists.

INSTRUMENT(S): LTQ Orbitrap Elite

ORGANISM(S): Escherichia Coli

SUBMITTER: Naveen Vankadari  

LAB HEAD: Chwan-Deng Hsiao

PROVIDER: PXD002705 | Pride | 2016-06-27

REPOSITORIES: Pride