Engineered single- and multi-cell chemotaxis pathways in E. coli.

Area of Science:

• Microbiology
• Synthetic Biology
• Biochemistry

Background:

• Chemotaxis is a fundamental cellular process enabling bacteria to navigate chemical gradients.
• Escherichia coli (E. coli) chemotaxis relies on specific attractant-receptor interactions.
• Engineering novel chemotactic responses requires modifying or introducing new molecular recognition pathways.

Purpose of the Study:

• To engineer the E. coli chemotaxis system to respond to non-native molecules.
• To develop synthetic enzymatic pathways that convert target molecules into E. coli chemoattractants.
• To create microbial consortia exhibiting complex, logic-gated chemotactic behavior.

Main Methods:

• Introduction of artificial enzymatic activity to convert target molecules into chemoattractant ligands.
• Utilizing native E. coli aspartate receptors with asparaginase for asparagine response.
• Employing penicillin acylase and engineered receptors for phenylacetyl glycine response.
• Exploiting the 'hitchhiker' effect to establish microbial consortia.

Main Results:

• Demonstrated robust chemotactic responses to novel attractants in both liquid and semisolid media.
• Successfully engineered E. coli to respond to asparagine and phenylacetyl glycine.
• Developed a microbial consortium exhibiting a logical 'AND' response to dual attractant gradients.
• Showcased the 'hitchhiker' effect for intercellular communication and coordinated cell movement.

Conclusions:

• The engineered chemotaxis system provides a versatile platform for expanding bacterial sensory capabilities.
• Synthetic biology approaches can create novel microbial behaviors and functional consortia.
• This work enables precise control over bacterial navigation and collective behavior in response to specific chemical cues.