Li Shuangxi, Li Lingcheng, Jiang Qiwu, Wang Jianfeng, Sun Xiaoming, Zhang Liangliang, Yuan Jianfeng
Xingzhi College, Zhejiang Normal University, Lanxi, China.
Key Laboratory of Wildlife Biotechnology and Conservation and Utilization of Zhejiang Province, Zhejiang Normal University, Jinhua, China.
Microb Biotechnol. 2025 Apr;18(4):e70149. doi: 10.1111/1751-7915.70149.
L-(+)-tartaric acid (L-TA) is a crucial hydroxy carboxylic chelator with extensive applications in the food and pharmaceutical industries. The synthesis of L-TA from renewable biomass presents a promising approach to mitigating environmental impact and advancing green energy initiatives. Previous studies revealed that a mutant transketolase (TKTA_M) could catalyse the production of tartaric semialdehyde, a precursor to L-TA. This study focuses on the development of a Gluconobacter oxydans cell factory for tartaric semialdehyde production, employing a combination of metabolic engineering and a modular strategy. The genetically modified G. oxydans T strain exhibited robust expression of the tktA_M gene. The optimal pH and temperature for this strain were determined to be 6.0°C and 30°C, respectively. Under these conditions, the strain produced 32.21 ± 0.74 g/L of tartaric semialdehyde from glucose. Implementation of a "Push-Pull" strategy enhanced tartaric semialdehyde production, resulting in a 23.85% increase in the G. oxydans T02 cell growth. In CSLP medium with 100 g/L glucose, the fermentation process yielded 48.88 ± 2.16 g/L of tartaric semialdehyde and 7.72 ± 1.56 g/L of residual 5-KGA after 48 h. This resulted in a tartaric semialdehyde productivity rate of 1.018 g/L·h, representing an 87.82% improvement over flask fermentation. This study demonstrates a straightforward and efficient microbial process for the oxidation of glucose to tartaric semialdehyde, indicating its potential for industrial-scale production and facilitating the synthesis of L-TA from renewable resources.
L-(+)-酒石酸（L-TA）是一种重要的羟基羧酸螯合剂，在食品和制药行业有广泛应用。从可再生生物质合成L-TA是减轻环境影响和推进绿色能源计划的一种有前景的方法。先前的研究表明，一种突变转酮醇酶（TKTA_M）可以催化L-TA前体酒石半醛的产生。本研究聚焦于开发一种用于生产酒石半醛的氧化葡萄糖酸杆菌细胞工厂，采用代谢工程和模块化策略相结合的方法。基因改造后的氧化葡萄糖酸杆菌T菌株表现出tktA_M基因的强劲表达。该菌株的最佳pH值和温度分别确定为6.0°C和30°C。在这些条件下，该菌株从葡萄糖中生产出32.21±0.74 g/L的酒石半醛。实施“推-拉”策略提高了酒石半醛的产量，导致氧化葡萄糖酸杆菌T02细胞生长增加了23.85%。在含有100 g/L葡萄糖的CSLP培养基中，发酵48小时后，发酵过程产生了48.88±2.16 g/L的酒石半醛和7.72±1.56 g/L的残留5-KGA。这导致酒石半醛生产率为1.018 g/L·h，比摇瓶发酵提高了87.82%。本研究展示了一种将葡萄糖氧化为酒石半醛的直接且高效的微生物过程，表明其在工业规模生产中的潜力，并有助于从可再生资源合成L-TA。
