Expression analysis of up-regulated genes responding to plumbagin in Escherichia coli

Jenn Wei Chen, Chang Ming Sun, Wei Lun Sheng, Yu Chen Wang, Wan Syu

Research output: Contribution to journalArticlepeer-review

23 Citations (Scopus)


Plumbagin is found in many medicinal plants and has been reported to have antimicrobial activities. We examined the molecular responses of Escherichia coli to plumbagin by using a proteomic approach to search for bacterial genes up-regulated by the drug. The protein profile obtained was compared with that of E. coli without the plumbagin treatment. Subsequent analyses of the induced proteins by mass spectroscopy identified several up-regulated genes, including ygfZ, whose function has not been defined. Analyses of the 5′-flanking sequences indicate that most of these genes contain a marbox-like stretch, and several of them are categorized as members of the mar/sox regulon. Representatives of these genes were cloned into plasmids, and the marbox-like sequences were modified by site-directed mutagenesis. It was proven that mutations in these regions substantially repressed the level of proteins encoded by the downstream genes. Furthermore, plumbagin's early effect was demonstrated to robustly induce SoxS rather than MarA, an observation distinctly different from that seen with sodium salicylate.

Original languageEnglish
Pages (from-to)456-463
Number of pages8
JournalJournal of Bacteriology
Issue number2
Publication statusPublished - 2006 Jan

All Science Journal Classification (ASJC) codes

  • Microbiology
  • Molecular Biology


Dive into the research topics of 'Expression analysis of up-regulated genes responding to plumbagin in Escherichia coli'. Together they form a unique fingerprint.

Cite this