2025年4月28日，厦门大学王远鹏团队在《美国化学会志》发表最新研究成果，他们利用工程奥奈达希瓦氏菌生物电合成直接将二氧化碳转化为苹果酸盐。

微生物电合成（MES）为二氧化碳稳定化提供了一种可持续的低碳方法，奥奈达希瓦氏菌（S. oneidensis）MR-1被确定为MES的理想微生物。然而，之前没有研究表明，S.oneidensis MR-1由于无法进行细胞内甲酸盐同化途径，可以直接将二氧化碳代谢为多碳（C₂₊）产物。 

研究组提供了将二氧化碳直接生物电化学还原为苹果酸C₄产物的初步概念验证证据。具体来说，二氧化碳转化为苹果酸的生产浓度达到了1.18 mmol·L^-1，这标志着直接C₄化合物生物电合成的首次出现。这种显著的CO₂到C₄的转化性能归因于在S.oneidensis MR-1中成功实施了双质粒系统，该系统促进了用于同化CO₂衍生甲酸盐的还原性甘氨酸途径（质粒I）和用于将代谢中间体引导到苹果酸生物合成的替代苹果酸生物合成途径（质粒II）的过表达。通过将二氧化碳稳定化推向碳负C₂₊生物制品，研究组在微生物中设计的复杂双质粒系统可以进一步改进，以实现可扩展的二氧化碳生物电解，从而促进工业应用。

附：英文原文

Title: Direct CO2 Transformation to Malate via Bioelectrosynthesis upon Engineered Shewanella oneidensis

Author: Yixin Li, Dong Xia, Yinuo Xie, Rong Dong, Mingfeng Cao, Qingbiao Li, Yuanpeng Wang

Issue&Volume: April 28, 2025

Abstract: Microbial electrosynthesis (MES) offers a sustainable and low-carbon approach for CO2 valorization, with Shewanella oneidensis (S. oneidensis) MR-1 identified as an ideal microbe for MES. However, no prior research has demonstrated that S. oneidensis MR-1 can directly metabolize CO2 into multicarbon (C2+) products due to its inability to perform the intracellular formate assimilation pathway. Here, we provide initial proof-of-concept evidence of direct bioelectrochemical CO2 reduction to the C4 product of malate. Specifically, the transformation of CO2 to malate attains a notable production concentration of 1.18 mmol·L–1, marking the first instance of direct C4 compound bioelectrosynthesis. Such remarkable CO2-to-C4 conversion performances are attributed to the successful implementation of dual-plasmid systems in S. oneidensis MR-1, which facilitate the overexpression of the reductive glycine pathway (Plasmid I) for assimilating CO2-derived formate and the alternative malate biosynthetic pathway (Plasmid II) to channel metabolic intermediates toward the biosynthesis of malate. Advancing CO2 valorization toward carbon-negative C2+ bioproducts, our sophisticated dual-plasmid systems engineered in microbes can be further refined for scalable CO2 bioelectrolysis with the objective of facilitating industrial applications.

DOI: 10.1021/jacs.5c01494

Source: https://pubs.acs.org/doi/abs/10.1021/jacs.5c01494