Programming the quorum sensing-based AND gate in Shewanella oneidensis for logic gated-microbial fuel cells

Area of Science:

• Synthetic biology
• Microbial electrochemistry
• Genetic engineering

Background:

• Quorum-sensing (QS) systems regulate gene expression based on cell density.
• Microbial fuel cells (MFCs) harness microbial metabolism for electricity generation.
• Extracellular electron transfer (EET) is crucial for MFC performance.

Purpose of the Study:

• To construct an AND logic gate using a synthetic QS module in Shewanella oneidensis MR-1.
• To enable controlled activation of extracellular electron transfer (EET).
• To develop AND-gated microbial fuel cells.

Main Methods:

• Construction of a synthetic QS-controlled AND logic gate in a Shewanella oneidensis MR-1 mtrA knockout mutant.
• Utilizing two input signals to activate the expression of the periplasmic decaheme cytochrome MtrA.
• Regeneration of the extracellular electron transfer conduit.

Main Results:

• Successfully implemented an AND logic gate based on synthetic QS.
• Demonstrated that two specific input signals are required for MtrA expression.
• Enabled the regeneration of the EET pathway in the mtrA knockout mutant.
• Facilitated the construction of AND-gated microbial fuel cells.

Conclusions:

• Synthetic QS modules can be effectively used to build logic gates in bacteria.
• AND logic gates provide a robust mechanism for controlling microbial functions like EET.
• This work advances the development of sophisticated microbial electrochemical systems.