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 Hsing, W.
Right arrow Articles by Silhavy, T. J.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Hsing, W.
Right arrow Articles by Silhavy, T. J.

 Previous Article  |  Next Article 

Journal of Bacteriology, September 1998, p. 4538-4546, Vol. 180, No. 17
0021-9193/98/$04.00+0
Copyright © 1998, American Society for Microbiology. All rights reserved.

Mutations That Alter the Kinase and Phosphatase Activities of the Two-Component Sensor EnvZ

Weihong Hsing,dagger Frank D. Russo,Dagger Karen K. Bernd,§ and Thomas J. Silhavy*

Department of Molecular Biology, Princeton University, Princeton, New Jersey 08544

Received 23 March 1998/Accepted 18 June 1998

EnvZ, a membrane receptor kinase-phosphatase, modulates porin expression in Escherichia coli in response to medium osmolarity. It shares its basic scheme of signal transduction with many other sensor-kinases, passing information from the amino-terminal, periplasmic, sensory domain via the transmembrane helices to the carboxy-terminal, cytoplasmic, catalytic domain. The native receptor can exist in two active but opposed signaling states, the OmpR kinase-dominant state (K+ P-) and the OmpR-P phosphatase-dominant state (K- P+). The balance between the two states determines the level of intracellular OmpR-P, which in turn determines the level of porin gene transcription. To study the structural requirements for these two states of EnvZ, mutational analysis was performed. Mutations that preferentially affect either the kinase or phosphatase have been identified and characterized both in vivo and in vitro. Most of these mapped to previously identified structural motifs, suggesting an important function for each of these conserved regions. In addition, we identified a novel motif that is weakly conserved among two-component sensors. Mutations that alter this motif, which is termed the X region, alter the confirmation of EnvZ and significantly reduce the phosphatase activity.

* Corresponding author. Mailing address: Department of Molecular Biology, Princeton University, Princeton, NJ 08544. Phone: (609) 258-5899. Fax: (609) 258-2769. E-mail: tsilhavy{at}molbio.princeton.edu.

dagger Present address: Small Molecule Therapeutics, Monmouth Junction, NJ 08852.

Dagger Present address: Incyte Pharmaceuticals, Palo Alto, CA 94304.

§ Present address: Botany Department, DCMB Group, Duke University, Durham, NC 27708.

Journal of Bacteriology, September 1998, p. 4538-4546, Vol. 180, No. 17
0021-9193/98/$04.00+0
Copyright © 1998, 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 © 1998 by the American Society for Microbiology. All rights reserved.