V MAFFENBEIER¹, J ROELOF VAN DER MEER<sup>1

1</sup>University of Lausanne, Department of Fundamental Microbiology

Two-component signaling systems interact with environmental stimuli upon which they trigger a cytoplasmic response. Their modular structure allows easy exchange of domains. The first functional chimeric transmembrane receptor (called TrzI) was constructed by Baumgartner et al. in 1994 by fusing the ligand binding domain of the chemoreceptor Trg to the kinase domain of the osmosensor EnvZ. Several other chimeras have been reported since but their functionality has not always been established. In order to be able to exploit the large natural diversity of bacterial chemoreceptors in simplified synthetic biosensor constructions, this thesis focuses on (I) understanding the requirements for the fusion site enabling chimera functionality, (II) predicting ligand-binding in chimeras, and (III) constructing functional biosensors with new specificities.