CHEMICAL ENGINEERING JOURNAL
·
2025
·
IF 13.2
Yongli Zhang,Zhao Zhou,Jun Wu,Yiyang Shi,Xinxiao Sun,Jia Wang,Xiaolin Shen,Qipeng Yuan
Methylation reactions are involved in the synthesis of various natural molecules, but the limited supply of intracellular S-adenosylmethionine (SAM) poses a challenge for the large-scale microbial production of methylated compounds. In this study, we conducted a comprehensive analysis and optimization of the SAM cycle regeneration pathway, enhancing the methylation efficiency in three key steps of the pathway (SAM carbon skeleton cycle, 5-methyltetrahydrofolate cycle, and adenine-ATP cycle), and constructed an efficient endogenous methylation platform in E. coli . This platform significantly increased the intracellular level of the cofactor SAM and improved methylation efficiency. Using this platform, the production of methylated products, including ferulic acid, vanillyl alcohol, and melatonin, increased by 4.2-fold, 1.28-fold, and 44.6 %, respectively. Notably, the ferulic acid titer reached 7.24 g/L, marking the highest level reported to date. These findings demonstrate the broad applicability of this methylation platform, providing a generalizable and effective approach for the biosynthesis of a wide range of SAM-dependent products.
研究领域:
生物工程
·
代谢工程
·
合成生物学
✓ 已验证
产品关联
DOI
高影响因子
Jove-Journal of Visualized Experiments
·
2019
·
IF 1.108
Zhiping Zhang,Shuhang Fan,Zhiqiang Chen,Yanzhi He,Mengfei Huang,Li Ding,Yanyan Zhang,Lin Chen,Xinyue Zhang
Flavonols are a major subclass of flavonoids with a variety of biological and pharmacological activities. Here, we provide a method for the in vitro enzymatic synthesis of a flavonol. In this method, Atf3h and Atfls1, two key genes in the biosynthetic pathway of the flavonols, are cloned and overexpressed in Escherichia coli. The recombinant enzymes are purified via an affinity column and then a bienzymatic cascade is established in a specific synthetic buffer. Two flavonols are synthesized in this system as examples and determined by TLC and HPLC/LC/MS analyses. The method displays obvious advantages in the derivation of flavonols over other approaches. It is time- and labor-saving and highly cost-effective. The reaction is easy to be accurately controlled and thus scaled up for mass production. The target product can be purified easily due to the simple components in the system. However, this system is usually restricted to the production of a flavonol from a flavanone.
研究领域:
生物化学
·
分子生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF MOLECULAR CATALYSIS B-ENZYMATIC
·
2013
·
IF 2.823
Xiaolin Pei,Lirong Yang,Gang Xu,Qiuyan Wang,Jianping Wu
Microbial nitrile hydratases (NHases) are important industrial catalysts to produce valuable amides. However, only some NHase genes have been reported and studied at the molecular level. In this study, we developed a genome mining method to discover Fe-type NHases from GenBank. The putative NHase gene from Pseudomonas putida F1 was cloned and functionally expressed in Escherichia coli BL21 (DE3) by assisting of a putative activator gene adjacent to β-subunit region. Three recombinant plasmids containing NHase gene or the activator gene were designed and constructed. Maximal enzyme activity was obtained when the structural and activator genes were transcribed as one unit in plasmid pCDFDuet-1 at 18 °C. However, the expressed product did not show any NHase activity when the downstream activator gene was ignored, and the product completely existed in insoluble inclusion body. The activator gene might be involved in protein folding of the α- and β-subunits of NHase. In addition, the Fe-type NHase exhibited broad substrate specificity. The enzyme can efficiently hydrate aromatic nitriles, such as 3-cyanopyridine, 4-cyanopyridine, and benzonitrile, asides from aliphatic nitriles preferentially. Therefore, the recombinant NHase shows potential applications in some amides preparation.
研究领域:
生物化学
·
微生物学
·
工业酶学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE
·
2016
·Vol. 52
·期 5
·2473-2483
·
IF 2.302
Zhu Lixia,Dai Jinyue,Chen Lai,Chen Jing,Na Haining,Zhu Jin
By covalently immobilizing imidazolium ion onto molecular chain, functional polyurethane (PU) is fabricated and thus an effective way is initiated to prepare electrospun membranes with antibacterial activity. In the experiment, PUs containing imidazolium ion side group (Bmim-PUs) are synthesized through a two-step polymerization process. It includes prepolymerization of isophorone diisocyanate (IPDI) with polyester glycol and chain extension polymerization using imidazolium-based ionic diol (Bmim-OH). Then, the obtained Bmim-PUs are electrospun into fibrous membranes with a diameter of ~640 nm. After a careful assessment, antibacterial activities of electrospun membranes against Gram-positive Staphylococcus aureus and Gram-negative Escherichia coli are clearly exhibited. The antibacterial efficiency of Bmim-PUs on both bacteria species improves by 60% in comparison with PU without imidazolium ion. This research suggests a simple but effective methodology to design and fabricate ultrafine fibrous membrane with significant antibacterial activity. Moreover, the obtained fibrous membranes have widely potential applications in protective textiles, filtration, and biomedical engineering.
研究领域:
材料科学
·
生物医学工程
✓ 已验证
产品关联
DOI
高影响因子
APPLIED MICROBIOLOGY AND BIOTECHNOLOGY
·
2023
·Vol. 107
·期 21
·6497-6506
·
IF 5
Liu Kun,Liu Yan,Li Xiangfei,Zhang Xiushan,Xue Zhenglian,Zhao Ming
Abstract The whole-cell catalysis strategy of alpha-ketoglutaric acid (α-KG) production from L-glutamic acid (L-Glu) using recombinant Escherichia coli , in which L-glutamate oxidase (LGox) was over-expressed, has replaced the traditional chemical synthesis strategy. However, large amounts of toxic by-product, H 2 O 2 , should be eliminated through co-expressing catalase (Cat), thus severely increasing burden in cells. To efficiently and economically produce α-KG, here, the genes SpLGox (from Streptomyces platensis NTU3304) and SlCat (from Streptomyces lividans TK24) were inserted into the low-dosage-IPTG (Isopropyl β-D-Thiogalactoside) inducible expression system, constructed in our previous work, in E. coli , respectively. Besides, a double-strain catalysis system was established and optimized to produce α-KG, and the productivity of α-KG was increased 97% compared with that through single strain catalysis. Finally, a double-strain cultivation strategy was designed and employed to simplify the scale-up fermentation. Using the optimized whole-cell biocatalyst conditions (pH 7.0, 35 °C), majority of the L-glutamic acid was transformed into α-KG and the titer reached 95.4 g/L after 6 h with the highest productivity at present. Therefore, this strategy may efficiently and cost-effectively produce α-KG, enhancing its potential for industrial applications. Key points
• SpLGox and SlCat were over-expressed to catalyze L-Glu to α-KG and eliminate by-product H
2
O
2
, respectively.
• Double-strain cultivation and catalysis system can efficiently and cost-effectively produce α-KG from L-Glu.
研究领域:
生物工程
·
代谢工程
·
酶学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF NANOPARTICLE RESEARCH
·
2014
·Vol. 16
·期 7
·1-12
·
IF 2.278
Zhao Lianhong,Yan Xiufang,Jie Zhiqiang,Yang Hong,Yang Shiping,Liang Jie
Regenerable antimicrobial N -halamine/silica hybrid nanoparticles (NPs) containing chlorinated 5,5-dimethylhydantoinyl (Cl-DMH) groups, Cl-DMH/SiO 2 hybrid NPs, have been prepared by a co-condensation reaction between N -(3-triethoxysilylpropyl)-5,5-dimethylhydantoin (TS-DMH) and tetraethoxysilane (TEOS) and then a chlorination reaction in NaClO solution. The as-synthesized Cl-DMH/SiO 2 NPs were characterized by transmission electron microscopy, Scanning electron microscopy, X-ray photoelectron spectra, Specific surface area, Differential scanning calorimetry, and Fourier transform infrared. Experimental results showed that the size of the as-synthesized Cl-DMH/SiO 2 NPs could be well adjusted by changing the mass ratio of TS-DMH/TEOS and the volume ratio of 28 % NH 4 OH/H 2 O. Antimicrobial tests showed that the as-prepared Cl-DMH/SiO 2 hybrid NPs had excellent antimicrobial activities against both Escherichia coli and Staphylococcus aureus . The minimum inhibitory concentration and minimum bactericidal concentration values of the as-prepared Cl-DMH/SiO 2 hybrid NPs are 15 and 20 μg/mL for S. aureus , 25 and 30 μg/mL for E. coli , respectively. Paper disk diffusion assay showed that smaller-sized Cl-DMH/SiO 2 hybrid NPs have bigger inhibition zone diameters, indicating stronger antimicrobial efficacies. Also, the storage stability and regenerability of Cl-DMH/SiO 2 hybrid NPs were investigated.
研究领域:
材料科学
·
微生物学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY
·
2025
·
IF 6.2
Xinlei Yuan,Fang Wu,Le Cheng,Tengteng Ji,Chenyan Zheng,Yumeng Ma,Yutong Jin,Jianguo Dong,Yan Jin,Bing Fang
The acceptable daily intake (ADI) and maximum residue limits in food for chlorpyrifos (CPF), a widely used organophosphorus pesticide, may damage the intestine. Here, we evaluated damage to the intestine by CPF at the ADI (0.01 mg/kg bodyweight/day) and at 10 times the ADI (10ADI; 0.1 mg/kg bodyweight/day) in mice after 8 weeks of exposure and evaluated the resulting immune response to an enterotoxigenic Escherichia coli (ETEC) infection. CPF at the ADI dose significantly disrupted the intestinal integrity and intestinal stem cell functionality, which may be associated with reduced indole-3-propionic acid levels. However, mice in the 10ADI group exhibited only elevated pro-inflammatory cell and cytokine levels. During ETEC infection, intestinal mucosal immunity was activated by the 10ADI dose, as indicated by increased regulatory T cells and IL-10 levels, which were associated with decreased fecal butyric acid content. Our study demonstrated that the effects of pesticide residues appear to be dose-specific, bringing attention to the health risk at the ADI level.
研究领域:
毒理学
·
免疫学
·
胃肠病学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Analytical Methods
·
2024
·Vol. 16
·期 28
·4865-4872
·
IF 2.7
Yujie Wen,Cong Tang,Qing Shen,Shuqing Dong,Yaya Wang,Yunchun Li,Shijun Shao
Developing an effective and convenient nitrite detection method is indispensable in food safety, environmental monitoring, clinical diagnosis of diseases, and many other areas. Herein, a dicyanoisophorone derivative, TMN-NH2 with large Stokes shift and near-infrared (NIR) emission, was proposed as a ratiometric fluorescence and colorimetric dual-mode probe for the rapid determination of NO2− in acidic media, showing excellent selectivity and high sensitivity. The sensing mechanism is based on the diazotization of TMN-NH2 with NO2− and subsequent diazonium salt hydrolysis to form a hydroxyl-substituted product (TMN-OH). Under the optimized conditions of reaction and detection, a new quantitative analysis method based on TMN-NH2 was established for NO2− detection, exhibiting good linear relationships to NO2− in the range of 0.5 to 15 μM with practical detection limits of 26.6 nM and 17.6 nM for the colorimetric and fluorescent readout, respectively. The quantitative detection of NO2− in real samples demonstrated satisfactory recoveries and repeatability. Moreover, TMN-NH2 was successfully applied for monitoring NO2− in Escherichia coli by confocal fluorescence imaging.
研究领域:
分析化学
·
食品安全
·
环境科学
·
医学诊断
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Microorganisms
·
2022
·Vol. 10
·期 3
·628
·
IF 4.926
Guosi Li,Fucheng Zhu,Peipei Wei,Hailong Xue,Naidong Chen,Baowei Lu,Hui Deng,Cunwu Chen,Xinjian Yin
Hyperoside (quercetin 3-O-galactoside) exhibits many biological functions, along with higher bioactivities than quercetin. In this study, three UDP-dependent glycosyltransferases (UGTs) were screened for efficient hyperoside synthesis from quercetin. The highest hyperoside production of 58.5 mg·L−1was obtained in a recombinantEscherichia colico-expressing UGT fromPetunia hybrida(PhUGT) and UDP-glucose epimerase (GalE, a key enzyme catalyzing the conversion of UDP-glucose to UDP-galactose) fromE. coli. When additional enzymes (phosphoglucomutase (Pgm) and UDP-glucose pyrophosphorylase (GalU)) were introduced into the recombinantE. coli, the increased flux toward UDP-glucose synthesis led to enhanced UDP-galactose-derived hyperoside synthesis. The efficiency of the recombinant strain was further improved by increasing the copy number of the PhUGT, which is a limiting step in the bioconversion. Through the optimization of the fermentation conditions, the production of hyperoside increased from 245.6 to 411.2 mg·L−1. The production was also conducted using a substrate-fed batch fermentation, and the maximal hyperoside production was 831.6 mg·L−1, with a molar conversion ratio of 90.2% and a specific productivity of 27.7 mg·L−1·h−1after 30 h of fermentation. The efficient hyperoside synthesis pathway described here can be used widely for the glycosylation of other flavonoids and bioactive substances.Keywords:hyperoside;quercetin;UDP-dependent glycosyltransferase;UDP-glucose;metabolic engineering
研究领域:
生物技术
·
代谢工程
·
生物化学
✓ 已验证
DOI
PubMed
高影响因子
Scientific Reports
·
2014
·Vol. 4
·期 1
·1-8
·
IF 5.078
Bai Yanfen,Bi Huiping,Zhuang Yibin,Liu Chang,Cai Tao,Liu Xiaonan,Zhang Xueli,Liu Tao,Ma Yanhe
Salidroside (1) is the most important bioactive component of Rhodiola (also called as “Tibetan Ginseng”), which is a valuable medicinal herb exhibiting several adaptogenic properties. Due to the inefficiency of plant extraction and chemical synthesis, the supply of salidroside (1) is currently limited. Herein, we achieved unprecedented biosynthesis of salidroside (1) from glucose in a microorganism. First, the pyruvate decarboxylase ARO10 and endogenous alcohol dehydrogenases were recruited to convert 4-hydroxyphenylpyruvate (2), an intermediate of L -tyrosine pathway, to tyrosol (3) in Escherichia coli . Subsequently, tyrosol production was improved by overexpressing the pathway genes and by eliminating competing pathways and feedback inhibition. Finally, by introducing Rhodiola -derived glycosyltransferase UGT73B6 into the above-mentioned recombinant strain, salidroside (1) was produced with a titer of 56.9 mg/L. Interestingly, the Rhodiola -derived glycosyltransferase, UGT73B6, also catalyzed the attachment of glucose to the phenol position of tyrosol (3) to form icariside D2 (4), which was not reported in any previous literatures.
研究领域:
生物化学
·
合成生物学
·
微生物学
✓ 已验证
DOI
PubMed
高影响因子
BIOTECHNOLOGY LETTERS
·
2015
·Vol. 38
·期 4
·619-627
·
IF 1.591
Zhuang Yibin,Jiang Jingjie,Bi Huiping,Yin Hua,Liu Shaowei,Liu Tao
Objectives To produce rosmarinic acid analogues in the recombinant Escherichia coli BLRA1, harboring a 4-coumarate: CoA ligase from Arabidopsis thaliana (At4CL) and a rosmarinic acid synthase from Coleus blumei (CbRAS). Results Incubation of the recombinant E. coli strain BLRA1 with exogenously supplied phenyllactic acid (PL) and analogues as acceptor substrates, and coumaric acid and analogues as donor substrates led to production of 18 compounds, including 13 unnatural RA analogues. Conclusion This work demonstrates the viability of synthesizing a broad range of rosmarinic acid analogues in E. coli , and sheds new light on the substrate specificity of CbRAS.
研究领域:
生物化学
·
合成生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
METABOLIC ENGINEERING
·
2016
·
IF 8.201
Yanfen Bai,Hua Yin,Huiping Bi,Yibin Zhuang,Tao Liu,Yanhe Ma
Gastrodin, a phenolic glycoside , is the key ingredient of Gastrodia elata , a notable herbal plant that has been used to treat various conditions in oriental countries for centuries. Gastrodin is extensively used clinically for its sedative, hypnotic, anticonvulsive and neuroprotective properties in China. Gastrodin is usually produced by plant extraction or chemical synthesis, which has many disadvantages. Herein, we report unprecedented microbial synthesis of gastrodin via an artificial pathway. A Nocardia carboxylic acid reductase , endogenous alcohol dehydrogenases and a Rhodiola glycosyltransferase UGT73B6 transformed 4-hydroxybenzoic acid, an intermediate of ubiquinone biosynthesis , into gastrodin in Escherichia coli. Pathway genes were overexpressed to enhance metabolic flux toward precursor 4-hydroxybenzyl alcohol. Furthermore, the catalytic properties of the UGT73B6 toward phenolic alcohols were improved through directed evolution. The finally engineered strain produced 545 mg l −1 gastrodin in 48 h. This work creates a new route to produce gastrodin, instead of plant extractions and chemical synthesis.
研究领域:
生物化学
·
合成生物学
·
药理学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）