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 Gosink, K. K.
Right arrow Articles by Parkinson, J. S.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Gosink, K. K.
Right arrow Articles by Parkinson, J. S.

 Previous Article  |  Next Article 

Journal of Bacteriology, May 2006, p. 3487-3493, Vol. 188, No. 10
0021-9193/06/$08.00+0     doi:10.1128/JB.188.10.3487-3493.2006
Copyright © 2006, American Society for Microbiology. All Rights Reserved.

Signaling Interactions between the Aerotaxis Transducer Aer and Heterologous Chemoreceptors in Escherichia coli

Khoosheh K. Gosink, Maria del Carmen Burón-Barral, and John S. Parkinson*

Biology Department, University of Utah, Salt Lake City, Utah 84112

Received 6 February 2006/ Accepted 3 March 2006

Aer, a low-abundance signal transducer in Escherichia coli, mediates robust aerotactic behavior, possibly through interactions with methyl-accepting chemotaxis proteins (MCP). We obtained evidence for interactions between Aer and the high-abundance aspartate (Tar) and serine (Tsr) receptors. Aer molecules bearing a cysteine reporter diagnostic for trimer-of-dimer formation yielded cross-linking products upon treatment with a trifunctional maleimide reagent. Aer also formed mixed cross-linking products with a similarly marked Tar reporter. An Aer trimer contact mutation known to abolish trimer formation by MCPs eliminated Aer trimer and mixed trimer formation. Trimer contact alterations known to cause epistatic behavior in MCPs also produced epistatic properties in Aer. Amino acid replacements in the Tar trimer contact region suppressed an epistatic Aer signaling defect, consistent with compensatory conformational changes between directly interacting proteins. In cells lacking MCPs, Aer function required high-level expression, comparable to the aggregate number of receptors in a wild-type cell. Aer proteins with clockwise (CW)-biased signal output cannot function under these conditions but do so in the presence of MCPs, presumably through formation of mixed signaling teams. The Tar signaling domain was sufficient for functional rescue. Moreover, CW-biased lesions did not impair aerotactic signaling in a hybrid Aer-Tar transducer capable of adjusting its steady-state signal output via methylation-dependent sensory adaptation. Thus, MCPs most likely assist mutant Aer proteins to signal productively by forming collaborative signaling teams. Aer evidently evolved to operate collaboratively with high-abundance receptors but can also function without MCP assistance, provided that it can establish a suitable prestimulus swimming pattern.


* Corresponding author. Mailing address: Biology Department, University of Utah, 257 South 1400 East, Salt Lake City, UT 84112. Phone: (801) 581-7639. Fax: (801) 581-4668. E-mail: Parkinson{at}biology.utah.edu.


Journal of Bacteriology, May 2006, p. 3487-3493, Vol. 188, No. 10
0021-9193/06/$08.00+0     doi:10.1128/JB.188.10.3487-3493.2006
Copyright © 2006, American Society for Microbiology. All Rights Reserved.




This article has been cited by other articles:

  • Mowery, P., Ostler, J. B., Parkinson, J. S. (2008). Different Signaling Roles of Two Conserved Residues in the Cytoplasmic Hairpin Tip of Tsr, the Escherichia coli Serine Chemoreceptor. J. Bacteriol. 190: 8065-8074 [Abstract] [Full Text]  
  • Ames, P., Zhou, Q., Parkinson, J. S. (2008). Mutational Analysis of the Connector Segment in the HAMP Domain of Tsr, the Escherichia coli Serine Chemoreceptor. J. Bacteriol. 190: 6676-6685 [Abstract] [Full Text]  
  • Dzinic, S. H., Shukla, M., Mandija, I., Ram, T. S., Ram, J. L. (2008). Variable length tandem repeat polyglutamine sequences in the flexible tether region of the Tsr chemotaxis receptor of Escherichia coli. Microbiology 154: 2380-2386 [Abstract] [Full Text]  
  • Schweinitzer, T., Mizote, T., Ishikawa, N., Dudnik, A., Inatsu, S., Schreiber, S., Suerbaum, S., Aizawa, S.-I., Josenhans, C. (2008). Functional Characterization and Mutagenesis of the Proposed Behavioral Sensor TlpD of Helicobacter pylori. J. Bacteriol. 190: 3244-3255 [Abstract] [Full Text]  
  • Watts, K. J., Johnson, M. S., Taylor, B. L. (2008). Structure-Function Relationships in the HAMP and Proximal Signaling Domains of the Aerotaxis Receptor Aer. J. Bacteriol. 190: 2118-2127 [Abstract] [Full Text]  
  • Amin, D. N., Taylor, B. L., Johnson, M. S. (2007). Organization of the Aerotaxis Receptor Aer in the Membrane of Escherichia coli. J. Bacteriol. 189: 7206-7212 [Abstract] [Full Text]  
  • del Carmen Buron-Barral, M., Gosink, K. K., Parkinson, J. S. (2006). Loss- and Gain-of-Function Mutations in the F1-HAMP Region of the Escherichia coli Aerotaxis Transducer Aer.. J. Bacteriol. 188: 3477-3486 [Abstract] [Full Text]