JB Track the topics, authors and articles important to you
Home Help [Feedback] [For Subscribers] [Archive] [Search] [Contents]
This Article
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow Copyright Information
Right arrow Books from ASM Press
Right arrow MicrobeWorld
Citing Articles
Right arrow Citing Articles via HighWire
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Soncini, F. C.
Right arrow Articles by Groisman, E. A.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Soncini, F. C.
Right arrow Articles by Groisman, E. A.

J. Bacteriol., 12 1996, 6796-6801, Vol 178, No. 23
Copyright © 1996, American Society for Microbiology

Two-component regulatory systems can interact to process multiple environmental signals

FC Soncini and EA Groisman
Department of Molecular Microbiology, Washington University School of Medicine, St. Louis, Missouri 63110, USA.

The PhoP/PhoQ two-component system of Salmonella typhimurium governs transcription of some 25 loci in response to the extracellular concentration of Mg2+. We have now identified one of these loci as pmrCAB, which codes for a two-component system that mediates resistance to the antibiotic polymyxin B. Transcription of seven of 25 PhoP- activated loci was dependent on a functional PmrA protein, the response regulator of the PmrA/PmrB system. Expression of the PmrA-dependent loci was induced by either Mg2+ limitation or mild acidification, whereas transcription of a PmrA-independent gene was activated by Mg2+ limitation but not acid pH. Induction of PmrA-activated genes by Mg2 limitation required the PhoP and PhoQ proteins. In contrast, the acid- mediated activation of PmrA-regulated genes occurred in strains that were missing either one of these proteins. Transcriptional regulation by a cascade of two-component systems allows pathogenic bacteria to express their virulence determinants in response to a broader spectrum of environmental cues.


This article has been cited by other articles:




Home Help [Feedback] [For Subscribers] [Archive] [Search] [Contents]
Appl. Environ. Microbiol. Infect. Immun. Eukaryot. Cell
Mol. Cell. Biol. J. Virol. Microbiol. Mol. Biol. Rev.
ALL ASM JOURNALS

Copyright © 1996 by the American Society for Microbiology. All rights reserved.