Engineering Hybrid Chemotaxis Receptors in Bacteria

Area of Science:

• Microbiology
• Biochemistry
• Molecular Biology

Background:

• Bacteria utilize transmembrane sensors, including chemotaxis receptors, to detect environmental stimuli and navigate chemical gradients.
• Escherichia coli chemotaxis receptors exhibit high sensitivity but have a limited natural ligand spectrum, restricting their use in biosensing.
• Developing novel chemoreceptors is crucial for expanding the sensing capabilities of E. coli for chemotaxis-based biosensor development.

Purpose of the Study:

• To engineer novel hybrid chemoreceptors by fusing E. coli chemotaxis receptor signaling domains with sensory domains from other species.
• To demonstrate the feasibility of creating functional hybrid receptors with extended ligand specificities.
• To establish a method for quantitatively characterizing ligand specificity of chemotaxis receptors and histidine kinases.

Main Methods:

• Constructing hybrid receptors by combining the E. coli receptor Tar with various sensory domains from chemotaxis receptors and two-component histidine kinases.
• Utilizing different fusion points to generate functional hybrid proteins.
• Employing standardized assays in E. coli to characterize ligand specificity.

Main Results:

• Successfully generated functional hybrid receptors by fusing the E. coli Tar receptor with diverse sensory domains.
• Demonstrated that hybrid receptors can be created using multiple fusion points.
• Showcased the utility of these hybrid receptors for quantitative characterization of ligand specificity.

Conclusions:

• Hybrid chemoreceptors can be effectively engineered by combining E. coli signaling domains with heterologous sensory domains.
• This approach enables the expansion of sensing capabilities beyond the natural repertoire of E. coli.
• The developed hybrid receptors provide a valuable tool for characterizing ligand specificities in chemotaxis receptors and histidine kinases for biosensor applications.