JB
Home Help [Feedback] [For Subscribers] [Archive] [Search] [Contents]
This Article
Right arrow Full Text
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 arrowReprints and Permissions
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 Härtig, E.
Right arrow Articles by Zumft, W. G.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Härtig, E.
Right arrow Articles by Zumft, W. G.

 Previous Article  |  Next Article 

Journal of Bacteriology, June 1999, p. 3658-3665, Vol. 181, No. 12
0021-9193/99/$04.00+0
Copyright © 1999, American Society for Microbiology. All rights reserved.

Nitrate and Nitrite Control of Respiratory Nitrate Reduction in Denitrifying Pseudomonas stutzeri by a Two-Component Regulatory System Homologous to NarXL of Escherichia coli

Elisabeth Härtig, Ulrike Schiek, Kai-Uwe Vollack, and Walter G. Zumft*

Lehrstuhl für Mikrobiologie der Universität zu Karlsruhe, Karlsruhe, Germany

Received 10 February 1999/Accepted 6 April 1999

Bacterial denitrification is expressed in response to the concurrent exogenous signals of low-oxygen tension and nitrate or one of its reduction products. The mechanism by which nitrate-dependent gene activation is effected was investigated in the denitrifying bacterium Pseudomonas stutzeri ATCC 14405. We have identified and isolated from this organism the chromosomal region encoding the two-component sensor-regulator pair NarXL and found that it is linked with the narG operon for respiratory nitrate reductase. The same region encodes two putative nitrate or nitrite translocases, NarK and NarC (the latter shows the highest similarity to yeast [Pichia] and plant [Nicotiana] nitrate transporters), and the nitrate-regulated transcription factor, DnrE, of the FNR family. The roles of NarX and NarL in nitrate respiration were studied with deletion mutants. NarL activated the transcription of narG, narK, and dnrE but did not affect the denitrification regulons for the respiratory substrates nitrite, nitric oxide, and nitrous oxide. The promoters of narG, narK, and dnrE carry sequence motifs, TACYYMT, which correspond to the NarL recognition sequence established for Escherichia coli. The cellular response toward nitrate and nitrite was mediated by the sensor protein NarX, which discriminated weakly between these oxyanions. Our data show that the NarXL two-component regulatory system has been incorporated into the bacterial denitrification process of P. stutzeri for selective regulation of nitrate respiration.

* Corresponding author. Mailing address: Lehrstuhl für Mikrobiologie, Universität Karlsruhe, PF 6980, D-76128 Karlsruhe, Germany. Phone: 49 (721) 6080. Fax: 49 (721) 608 4290. E-mail: dj03{at}rz.uni-karlsruhe.de.

Journal of Bacteriology, June 1999, p. 3658-3665, Vol. 181, No. 12
0021-9193/99/$04.00+0
Copyright © 1999, American Society for Microbiology. All rights reserved.


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 © 1999 by the American Society for Microbiology. All rights reserved.