This Article Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Copyright Information Books from ASM Press MicrobeWorld Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Batchelor, E. Articles by Goulian, M. Search for Related Content PubMed PubMed Citation Articles by Batchelor, E. Articles by Goulian, M.

Continuous Control in Bacterial Regulatory Circuits

Department of Physics,¹ Institute for Medicine and Engineering, University of Pennsylvania, Philadelphia, Pennsylvania,³ Department of Molecular Biology, Princeton University, Princeton, New Jersey²

Received 14 June 2004/ Accepted 17 August 2004

We show that for two well-characterized regulatory circuits in Escherichia coli, Tn10 tetracycline resistance and porin osmoregulation, the transcriptional outputs in individual cells are graded functions of the applied stimuli. These systems are therefore examples of naturally occurring regulatory circuits that exhibit continuous control of transcription. Surprisingly, however, we find that porin osmoregulation is open loop; i.e., the porin expression level does not feed back into the regulatory circuit. This mode of control is particularly interesting for an organism such as E. coli, which proliferates in diverse environments, and raises important questions regarding the biologically relevant inputs and outputs for this system.

This article has been cited by other articles:

• Shinar, G., Milo, R., Martinez, M. R., Alon, U. (2007). Input output robustness in simple bacterial signaling systems. Proc. Natl. Acad. Sci. USA 104: 19931-19935 [Abstract] [Full Text]  
• Miyashiro, T., Goulian, M. (2007). Stimulus-dependent differential regulation in the Escherichia coli PhoQ PhoP system. Proc. Natl. Acad. Sci. USA 104: 16305-16310 [Abstract] [Full Text]  
• Podbielski, A. (2007). Flexible Architecture of the Streptococcus pyogenes FCT Genome Region: Finally the Clue for Understanding Purulent Skin Diseases and Long-Term Persistence?{triangledown}. J. Bacteriol. 189: 1181-1184 [Full Text]  
• Begic, S., Worobec, E. A. (2006). Regulation of Serratia marcescens ompF and ompC porin genes in response to osmotic stress, salicylate, temperature and pH. Microbiology 152: 485-491 [Abstract] [Full Text]  
• Kreikemeyer, B., Nakata, M., Oehmcke, S., Gschwendtner, C., Normann, J., Podbielski, A. (2005). Streptococcus pyogenes Collagen Type I-binding Cpa Surface Protein: EXPRESSION PROFILE, BINDING CHARACTERISTICS, BIOLOGICAL FUNCTIONS, AND POTENTIAL CLINICAL IMPACT. J. Biol. Chem. 280: 33228-33239 [Abstract] [Full Text]  
• Batchelor, E., Walthers, D., Kenney, L. J., Goulian, M. (2005). The Escherichia coli CpxA-CpxR Envelope Stress Response System Regulates Expression of the Porins OmpF and OmpC. J. Bacteriol. 187: 5723-5731 [Abstract] [Full Text]  
• Fang, F. C. (2005). Sigma cascades in prokaryotic regulatory networks. Proc. Natl. Acad. Sci. USA 102: 4933-4934 [Full Text]