METABOLIC ENGINEERING
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2024
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IF 6.8
Qingchen Li,Chenxi Li,Jie Zhong,Yukun Wang,Qinghua Yang,Bingmei Wang,Wenjin He,Jianzhong Huang,Shengyuan Lin,Feng Qi
N-methylserotonin (NMS) is a valuable indole alkaloid with therapeutic potential for psychiatric and neurological disorders, and it is used in health foods, cosmetics, and weight loss supplements. However, environmental challenges and low reaction efficiencies significantly hinder cost-effective, large-scale production of NMS in plants or through chemical synthesis. Herein, we have successfully engineered Escherichia coli strains to enhance NMS production from L-tryptophan using whole-cell catalysis. We developed multiple biosynthesis pathways incorporating modules for serotonin (5-hydroxytryptamine, 5-HT), tetrahydromonapterin (MH₄), and S-adenosylmethionine (SAM) synthesis. To enhance MH₄ availability, we employed a high-activity Bacillus subtilis FolE and minimized carbon flux loss through targeted gene knockouts in competitive metabolic pathways, improving 5-HT production. Additionally, we constructed a comprehensive SAM biosynthesis module to facilitate transmethylation by a selected N-methyltransferase fused with ProS2. These engineered modules were coexpressed in two plasmids within the optimized strain NMS-19, producing 128.6 mg/L of NMS in a 5-L bioreactor using fed-batch cultivation—a 92-fold increase over the original strain. This study introduces a viable strategy for NMS production and provides insights into the biosynthesis of SAM-dependent methylated tryptamine derivatives.
研究领域:
生物技术
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代谢工程
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微生物学
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药理学
✓ 已验证
DOI
PubMed
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
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2025
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IF 8.5
Yamiao Li,Jingxin Rao,Zhentao Jiang,Xinyi Zhang,Qiang Zhu,Caokai Zhu,Wenli Yu,Xin Dong,Shanshan Gao,Wenchi Zhang,Liang Lin,Mingyue Zheng,Rongzhen Zhang
Ergothioneine (ERG), a sulfur-containing natural antioxidant with significant biomedical potentials, has long been limited by low productivity in microbial fermentation. Here, we report the first high-efficiency in vitro reconstruction of a multi-enzyme cascade for ERG biosynthesis. To address the rate-limiting histidine methylation step, we employed a synergistic strategy integrating machine learning–based kinetic prediction (CataPro, DLkcat), molecular dynamics simulations, and conformational dynamics analysis to guide site-directed mutagenesis of Mycolicibacrterium smegmatis EgtD. This yielded a triple mutant M3 (L53A/T59S/E282S) with 3.4- and 2.8-fold enhancements in catalytic efficiency ( k cat / K m ) toward histidine and S-adenosyl-L-methionine (SAM), respectively. Mechanistically, M3 enhances catalysis by reducing the SAM-histine distance, optimizing the catalytic angle, eliminating non-productive hydrogen bonds, and unlocking a secondary ligand tunnel through a mutation-induced gating mechanism. When coupled with a SAM-regeneration module, the engineered cascade enables preparative-scale ERG synthesis, reaching a titer of 6.05 g·L −1 within 14.5 h and productivity of 10.01 g·L −1 d −1 —the highest report to date. This work showcases a structure-guided, AI-assisted approach that overcomes evolutionary constraints, unlocks latent reactivity, and accelerates the development of efficient biocatalytic cascades for high-value compound synthesis.
研究领域:
合成生物学
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酶工程
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计算生物学
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生物催化
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代谢工程
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结构生物学
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机器学习在生物技术中的应用
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Nano Today
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2024
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IF 13.2
Dan Lu,Qi Wu,Xuanshou Xu,Qi Lyu,Chang Liu,Haixia Yuan,Minfeng Huo,Huixiong Xu,Liying Wang
Acute colitis is characterized by the microenvironment with a high level of inflammation, oxidative stress as well as a disordered microbiome . Sustained delivery of the therapeutic medicine into the colitis foci is limited due to the harsh condition of the gastric environment and fast excretion kinetics in the gut. Herein, we have designed an orally administrable probiotic inulin gel (igel) containing living Bacillus subtilis ( B. subt ) engineered with outperformed antioxidative single manganese atomic nanocatalyst (SAM NCs) for effective, sustained, and biocompatible therapeutics against acute colitis. Based on the multi-catalytic antioxidative activities (superoxide dismutase, glutathione peroxidase, and catalase) of the synthetic SAM NCs, these nanocatalysts are capable of eliminating the oxidative stresses both in vitro and in vivo . With further engineering onto the living Bacillus subtilis and subsequent in situ gelation inside the inulin, the as-formed probiotic igel(SAM NCs@ B. subt ) could effectively target and colonize inside the colon region, triggering the in vivo anti-inflammatory, anti-oxidative and gut microbiome modulation performance with high biocompatibility. The present study provides a promising probiotic gelation therapeutic strategy against acute colitis, shedding light on the exploration and clinical transformation of gastrointestinal disease.
研究领域:
胃肠病学
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纳米技术
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药剂学
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微生物学
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生物医学工程
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）