The promoter architectural landscape of the Salmonella PhoP regulon

Igor Zwir, Tammy Latifi, J. Christian Perez, Henry Huang, Eduardo A. Groisman

Research output: Contribution to journalArticlepeer-review

67 Scopus citations


The DNA-binding protein PhoP controls virulence and Mg 2+ homeostasis in the Gram-negative pathogen Salmonella enterica serovar Typhimurium. PhoP regulates expression of a large number of genes that differ both in their ancestry and in the biochemical functions and physiological roles of the encoded products. This suggests that PhoP-regulated genes are differentially expressed. To understand how a bacterial activator might generate varied gene expression behaviour, we investigated the cis-acting promoter features (i.e. the number of PhoP binding sites, as well as their orientation and location with respect to the sites bound by RNA polymerase and the sequences that constitute the PhoP binding sites) in 23 PhoP-activated promoters. Our results show that natural PhoP-activated promoters utilize only a limited number of combinations of cis-acting features - or promoter architectures. We determine that PhoP activates transcription by different mechanisms, and that ancestral and horizontally acquired PhoP-activated genes have distinct promoter architectures.

Original languageEnglish
Pages (from-to)463-485
Number of pages23
JournalMolecular Microbiology
Issue number3
StatePublished - May 2012


Dive into the research topics of 'The promoter architectural landscape of the Salmonella PhoP regulon'. Together they form a unique fingerprint.

Cite this