Study of the TmoS/TmoT two-component system: towards the functional characterization of the family of TodS/TodT like systems.
Bottom Line: Tightest ligand binding was observed for toluene (K(D) = 150 nM), which corresponds to the highest affinity measured between an effector and a sensor kinase.Other TmoS ligands, termed antagonists, failed to increase TmoS autophosphorylation, which resulted in their incapacity to stimulate gene expression in vivo.Among these ligands, toluene was the most potent inducer of both promoter activities.
Affiliation: Department of Environmental Protection, Estación Experimental del Zaidín, Consejo Superior de Investigaciones Científicas, C/ Prof. Albareda 1, Granada, Spain. .Show MeSH
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Mentions: During evolution genes of prototypal TCSs have fused to more complex systems referred to as phosphorelay TCS (Whitworth and Cock, 2009), which employ a His1‐Asp1‐His2‐Asp2 phosphorylation cascade. Phosphorelay systems so far studied include for example the ArcBA, TorSR and EvgSA systems of Escherichia coli (Perraud et al., 1999; Malpica et al., 2006), the BvgST system of Bordetella sp. (Beier and Gross, 2008) or the sporulation phosphorelay of Bacillus subtilis (Burbulys et al., 1991). All of these systems were classified as TRPR systems (Fig. 1), implying that the relay involves consecutive phosphorylation of a transmitter module, followed by a first receiver domain, a histidine containing phosphotransfer domain and a second receiver domain (Williams and Whitworth, 2010). A transmitter module is composed of a dimerization and histidine phosphotransfer domain and a catalytic domain that catalyses transmitter module autophosphorylation using ATP as phosphoryldonor. However, genome analyses indicated that there is a different type of phosphorelay system, termed TRTR, which contain two transmitter modules and two receiver domains (Fig. 1). At the genetic level it was shown that TRTR systems are as abundant as the TRPR systems (Williams and Whitworth, 2010). However, at the functional level there is little data available on this type of system.
Affiliation: Department of Environmental Protection, Estación Experimental del Zaidín, Consejo Superior de Investigaciones Científicas, C/ Prof. Albareda 1, Granada, Spain. .