P22-based challenge phage constructs to study protein-protein interactions between the σ54-dependent promoter, dctA, and its transcriptional regulators

Jeong Min Song, Eungbin Kim, Joon H. Lee

Research output: Contribution to journalArticle


To study interactions between C4-dicarboxylic acid transport protein D and Eσ54 in the dctA promoter regulatory region, we used the challenge phage system. An ant'-'lac fusion was recombined onto the challenge phage, and this ant'-'lac fusion along with Pant and the R. meliloti dctA promoter regulatory region were cloned onto a plasmid. The plasmid bearing the ant'-'lac fusion was used as a reporter plasmid in a coupled transcription-translation system. Addition of purified σ54 to the coupled system specifically repressed transcription of the plasmid-borne ant'-'lac fusion. When DCTD was added along with σ54 to the coupled system, transcription of the ant'-'lac fusion was even further repressed, suggesting that DCTD may stabilize closed complexes between Eσ54 and the dctA promoter.

Original languageEnglish
Pages (from-to)205-210
Number of pages6
JournalJournal of Microbiology
Issue number3
Publication statusPublished - 2002 Sep 1


All Science Journal Classification (ASJC) codes

  • Microbiology
  • Applied Microbiology and Biotechnology

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