Multi-Skalen-Modellierung der Signaltransduktion bei E. coli Chemotaxis

• Applicants: Professor Dr. Dirk Lebiedz; Professor Dr. Victor Sourjik
• Subject Area: Bioinformatics and Theoretical Biology
• Term: from 2005 to 2007
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 15948989

• Final Report Year: 2008

Final Report Abstract

Chemotaxis in Escherichia coli is one of the best-studied models for signal transduction in biology, with analogues of its components being found in many other networks. The pathway is noted for its high sensitivity, wide dynamic range, and robustness, and is thus an attractive model for the detailed quantitative analysis of signal transduction. At its core are sensory complexes that include transmembrane receptors and the associated kinase CheA, and form macromolecular clusters that amplify and integrate chemotactic signals. The pathway also includes an adaptation system, which adjusts the activity and sensitivity of the sensory complexes by receptor methylation and is necessary to ensure robust signalling output under conditions of external or internal perturbations. In this project, we quantitatively analyzed spatial distribution of sensory clusters and their dynamics. Combined with quantitative modeling it offered deeper insights in the pathway regulation, and provided a valuable information for the future computer modeling efforts. In particular, our results demonstrate that cluster positioning and dynamics have been evolutionary optimized to enable optimal performance. The project results have been published in such high-profile journals as PNAS, EMBO J, and Molecular Microbiology.

Publications

• (2006) Determinants of chemoreceptor cluster formation in Escherichia coll. Mol. Microbiol., 61: 407-417.
  Kentner, D., Thiem, S., Hildenbeutel, M. and Sourjik, V.
  
• (2007) Positioning of chemosensory clusters in E co//and its relation to cell division. EMBOJ., 26:1615-1623.
  Thiem, S., Kentner, D. and Sourjik, V.
  
• (2008) Protein exchange dynamics at chemoreceptor clusters in Escherichia coll. Proc. Natl. Acad. Sei. USA, 105: 6403-6408.
  Schulmeister, S., Ruttorf, M., Thiem, S., Kentner, D., Lebiedz, D. and Sourjik, V.
  
• (2008) Stochastic assembly of chemoreceptor clusters in Escherichia coll. Mol. Microbiol., 68:1228-1236.
  Thiem, S. and Sourjik, V.