2023-09-11 スイス連邦工科大学ローザンヌ校(EPFL)
◆研究の主要な革新は、E. coli内に完全な電子伝達経路を構築したことで、これにより電流の発生が通常の方法に比べて3倍向上しました。また、この遺伝子組み換えE. coliは、廃水処理やエネルギー生産など幅広いアプリケーションに活用できる可能性があり、持続可能な技術開発に対する多様なツールとして活用されるでしょう。
<関連情報>
- https://actu.epfl.ch/news/bacteria-generate-electricity-from-wastewater/
- https://www.cell.com/joule/fulltext/S2542-4351(23)00352-5
改変大腸菌の電気活性を高める細胞外電子伝達経路 Extracellular electron transfer pathways to enhance the electroactivity of modified Escherichia coli
Mohammed Mouhib,Melania Reggente,Lin Li,Nils Schuergers,Ardemis A. Boghossian
Joule Published:September 08, 2023
DOI:https://doi.org/10.1016/j.joule.2023.08.006
Highlights
•Expression of cytochromes enhances the electroactivity of Escherichia coli
•Pathway composition determines electron transfer rates
•Periplasmic electron shuttling is essential for high electroactivity
•Thus engineered E. coli are a promising chassis for microbial electrochemical devices
Summary
Escherichia coli (E. coli) show limited extracellular electron transfer (EET) that compromises their use in bioelectronics. We enhance the EET in E. coli by expressing an electron transfer pathway that spans the inner and outer membranes of the cell, including the periplasmic space in between. We observe a 54% enhancement in electron transfer for engineered E. coli expressing the endogenous inner-membrane NapC and periplasmic NapB cytochromes under non-native conditions with the outer-membrane MtrCAB complex from Shewanella oneidensis (S. oneidensis). The greatest enhancement, however, is observed for E. coli expressing the complete S. oneidensis Mtr pathway consisting of the inner-membrane CymA, periplasmic small tetraheme cytochrome (STC), and outer-membrane Mtr complex. This engineered strain shows a 3-fold increase in current generation compared with the empty vector control and a 2-fold increase compared with the state-of-the-art bioengineered strain comprising only the Mtr complex and CymA. These results highlight the importance of periplasmic shuttles in engineering EET.
