Marine Biofilm Engineered to Produce Current in Response to Small Molecules

Area of Science:

• Microbiology
• Synthetic Biology
• Environmental Biotechnology

Background:

• Engineered electroactive bacteria offer potential for sensing and biosynthesis.
• Functional expression of electron transfer modules in bacteria adapted to non-freshwater environments is crucial for practical applications.

Purpose of the Study:

• To demonstrate functional expression of the Shewanella oneidensis electron transfer pathway in the marine bacterium Marinobacter atlanticus.
• To engineer M. atlanticus for electrical signal-based environmental sensing and response in artificial seawater.

Main Methods:

• Genetic engineering of Marinobacter atlanticus to express the Shewanella oneidensis electron transfer pathway.
• Utilizing genetically encoded sensors for controlled protein expression in planktonic and biofilm cells.
• Assessing current production and electron transfer reversibility in artificial seawater.

Main Results:

• Significant current production was achieved in M. atlanticus upon addition of menaquinone, which is essential for electron transfer.
• Electrical current was observed through the S. oneidensis pathway in M. atlanticus during biofilm formation when inducing molecules were present.
• Reversible electron transfer indicated controllable electrical signaling into M. atlanticus.

Conclusions:

• Marine bacterium M. atlanticus can be genetically engineered for electrical signal-based environmental sensing and response.
• Successful transfer and function of the S. oneidensis electron transfer pathway in a marine host demonstrate feasibility for relevant conditions.
• This work advances the development of electroactive bacteria for operationally relevant environmental applications.