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 Zhang, Y.
Right arrow Articles by Roberts, G. P.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Zhang, Y.
Right arrow Articles by Roberts, G. P.

Journal of Bacteriology, November 2001, p. 6159-6168, Vol. 183, No. 21
0021-9193/01/$04.00+0   DOI: 10.1128/JB.183.21.6159-6168.2001
Copyright © 2001, American Society for Microbiology. All rights reserved.

Functional Characterization of Three GlnB Homologs in the Photosynthetic Bacterium Rhodospirillum rubrum: Roles in Sensing Ammonium and Energy Status

Yaoping Zhang,1,2,3 Edward L. Pohlmann,1,3 Paul W. Ludden,2,3 and Gary P. Roberts1,3,*

Departments of Bacteriology1 and Biochemistry2 and Center for the Study of Nitrogen Fixation,3 University of Wisconsin-Madison, Madison, Wisconsin 53706

Received 26 February 2001/Accepted 2 August 2001

The GlnB (PII) protein, the product of glnB, has been characterized previously in the photosynthetic bacterium Rhodospirillum rubrum. Here we describe identification of two other PII homologs in this organism, GlnK and GlnJ. Although the sequences of these three homologs are very similar, the molecules have both distinct and overlapping functions in the cell. While GlnB is required for activation of NifA activity in R. rubrum, GlnK and GlnJ do not appear to be involved in this process. In contrast, either GlnB or GlnJ can serve as a critical element in regulation of the reversible ADP ribosylation of dinitrogenase reductase catalyzed by the dinitrogenase reductase ADP-ribosyl transferase (DRAT)/dinitrogenase reductase-activating glycohydrolase (DRAG) regulatory system. Similarly, either GlnB or GlnJ is necessary for normal growth on a variety of minimal and rich media, and any of the proteins is sufficient for normal posttranslational regulation of glutamine synthetase. Surprisingly, in their regulation of the DRAT/DRAG system, GlnB and GlnJ appeared to be responsive not only to changes in nitrogen status but also to changes in energy status, revealing a new role for this family of regulators in central metabolic regulation.

* Corresponding author. Mailing address: Department of Bacteriology, University of Wisconsin-Madison, Madison, WI 53706. Phone: (608) 262-3567. Fax: (608) 262-9865. E-mail: groberts{at}bact.wisc.edu.

Journal of Bacteriology, November 2001, p. 6159-6168, Vol. 183, No. 21
0021-9193/01/$04.00+0   DOI: 10.1128/JB.183.21.6159-6168.2001
Copyright © 2001, 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 © 2001 by the American Society for Microbiology. All rights reserved.