JOURNAL OF BIOTECHNOLOGY
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2015
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IF 2.871
Yue-De Cao,Yu-Cai He,Hao Li,Guo-Yin Kai,Jian-He Xu,Hui-Lei Yu
Hyoscyamine 6 β -hydroxylase (H6H, EC 1.14.11.11), an α-ketoglutarate dependent dioxygenase catalyzes the hydroxylation of (−)-hyoscyamine and the subsequent epoxidation of 6 β -hydroxyhyoscyamine to form scopolamine, a valuable natural alkaloid. In this study, random mutagenesis and site-directed saturation mutagenesis were used to enhance the hydroxylation activity of H6H from Anisodus acutangulus ( Aa H6H). A double mutant, Aa H6H M1 (S14P/K97A), showed a 3.4-fold improved hydroxylation activity compared with the wild-type enzyme, and the in vivo epoxidation activity was also improved by 2.3 times. After 34 h cultivation of Escherichia coli cells harboring Aa h6h m1 in a 5-L bioreactor with a working volume of 3 L, scopolamine was produced via a single-enzyme-mediated two-step transformation from 500 mg L −1 (−)-hyoscyamine in 97% conversion, and 1.068 g of the product were isolated, corresponding to a space-time yield of 251 mg L −1 d −1 . This study shows that the protein engineering of some key enzymes is a promising and effective way for improving the production of rare natural products such as scopolamine.
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Journal of Materials Chemistry B
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2017
·Vol. 5
·期 20
·3728-3738
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IF 4.543
Tong Liu,Ruiying Huang,Juchang Zhong,Yikun Yang,Zhikai Tan,Weihong Tan
The ideal 3D scaffold for biological applications has not yet been designed. Our aim is to better match the scaffold performance through fine control of the fabrication process. Here, we applied electro-hydrodynamic jet (E-jet) 3D printing technology using poly-(lactic-co-glycolic acid) (PLGA) solution to construct scaffolds for tissue engineering applications. We fabricated different scaffolds of 1 : 1, 1 : 2 and 1 : 3 aspect ratios and tested the biological compatibility of the 2D and 3D printed scaffolds with fibroblasts. The scaffolds were used to culture fibroblasts, the main cellular components of loose connective tissue. The results show that the E-jet printed scaffolds could guide and improve cell growth. These scaffolds were able to support cellular alignment and proliferation. The cell angle was consistent with the longitudinal direction of the scaffolds, potentially enhancing the wound healing performance. Thus, the potential of this flexible technology for the 3D printing of scaffolds for the engineering of tissues is extensive.
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BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS
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2025
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IF 2.2
Youming Shi,Wenjiao Gu,Yujie Wei,Shuangyi Li,Shining Zhang,Ying jiang,Chuanjian Chen,Ting Liu,Limei Shuai,Xiaochun Zhou,Futian Tang
Purpose Atherosclerosis (AS) and atherosclerotic calcification (AC) are closely related to the cardiovascular diseases, largely due to its induction of vasomotor dysfunction. We previously reported that Calpain-1 inhibitor attenuated AS and AC. The present study was designed to investigate the effects and potential mechanisms of Calpain-1 knockout (Calpain-1 KO) in Apolipoprotein E KO (ApoE KO) mice on AS, AC, aortic vasomotor function as well as the liver dysfunction. Methods We hybridized ApoE KO mice with Calpain-1 KO mice to obtain ApoE /Calpain-1 double KO (A×C DKO) mice. The formation of AS and AC was evaluated and liver function was determined. Aortic vasomotor function was assessed. Contents of TNF-α, IL-6, IL-18, IL-1β and NO and the activity of AST, ALT, ALP and eNOS in serum were quantified. The mRNA expression of CD68, SR-A, CD36, PPAR-γ, LXR-α, ABCA1, BMP-2, OPN, ALP and Runx2 in aorta and/or liver were measured. Results The results showed that in comparison to C57 mice, ApoE KO mice demonstrated the significant increases in the areas of AS and AC, the increases in the mRNA expression of CD68 in the aorta, the increases in the AST, ALT and ALP activity in serum. ApoE KO mice also showed the dysfunction of the aortic contraction induced by phenylephrine and of the relaxation induced by acetylcholine. However, compared with ApoE KO mice, A×C DKO mice exhibited the significant attenuation of AS and AC and the downregulation of mRNA expression of CD68 in aorta. A×C DKO mice revealed the reduction of AST, ALT and ALP activity in serum, the improvements in aortic contraction and relaxation as well as the increases in eNOS activity and NO content in serum. A×C DKO mice also showed the decreases in the contents of TNF-α, IL-6, IL-18 and IL-1β in serum. The mRNA expression of CD68 in aorta, SR-A and CD36 in both aorta and liver of A×C DKO mice was downregulated, while that of PPAR-γ, LXR-α, and ABCA1 was upregulated in comparison of ApoE KO mice. In addition, the mRNA expression of BMP-2, OPN, ALP and Runx2 in aorta of A×C DKO mice was downregulated in comparison of ApoE KO mice. Conclusion The results suggested that deficiency of Calpain-1 attenuated the formation of AS and AC and improved vasomotor and liver dysfunction in ApoE KO mice through anti-inflammation, and modulation of the mRNA expression of genes related to AS and AC.
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EUROPEAN FOOD RESEARCH AND TECHNOLOGY
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2024
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IF 3
Chen Ziqiang,Ma Mingtao,Chen Xingguang,Peng Zhengcong,Liu Hua,Lu Jian,Wu Dianhui
The process of aging was crucial in enhancing the aroma quality of Huangjiu. Gas chromatography electronic nose (GC-E-Nose), gas chromatography-mass spectrometry (GC–MS), and gas chromatography-ion mobility spectrometry (GC-IMS) were employed to detect the variations in aroma among five samples aged for varying years (5–11). A comprehensive analysis revealed the presence of 85 compounds in the Shaoxing Huangjiu, twenty of which were identified as crucial contributors to its flavor profile through odor activity values analysis. The volatile aroma components of Huangjiu exhibited notable variations among different aging years. Additionally, the concentration and diversity of key aroma compounds increased with prolonged aging. At the same time, quantitative descriptive sensory analysis showed that aging could enhance the ester and acid aroma of Huangjiu. Moreover, based on variable importance for the projection, seven potential aroma markers such as diethyl succinate, ethyl butyrate, and furfural were screened out, which were the major compounds that caused the flavor differences of aged Huangjiu. The results offer valuable theoretical support for illustrating and regulating the quality of Huangjiu during its aging process.
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ANALYTICA CHIMICA ACTA
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2024
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IF 5.7
Zesen Zuo,Kai Liu,Chunqiong Wang,Shengbao He,Fei Yang,Fengqin Chang,Wen-Tong Chen,Guangzhi Hu
Background The heavy metal ion Cd 2+ is acutely toxic, and excessive concentrations can have adverse effects on human production and life, and even lead to significant public health risks and environmental impacts. There are several mature non-electrochemical methods for heavy metal detection, but these methods are characterized by high cost, which makes it difficult to be applied to the field for timely detection. Therefore, it is necessary to prepare a new electrochemical sensor that is environmentally friendly and capable of detecting Cd 2+ in the environment quickly, easily and sensitively. Results In this study, hydrogen-bonded organic frameworks (HOFs) were synthesized by a simple hydrothermal reaction. The prepared materials consisted of only C, N and O and had a thin lamellar structure. The HOFs were integrated into a novel electrochemical sensor to achieve accurate detection of Cd 2+ ions in real aqueous environments by square wave anodic dissolution voltammetry. The sensor has a wide linear range and a detection limit as low as 0.13 μg/L. Several real water samples, such as tap water, lake water, and e-cigarette digest, were analyzed to simulate the working environment of the sensor, and the results showed that the recoveries of Cd 2+ ranged from 95.75 % to 101.2 %. Significance We pioneered the detection of heavy metal ions Cd 2+ in e-cigarette digestate samples with the innovative use of HOFs as the sensor material, which demonstrated the potential application in electrochemical sensing with extremely low background current value and high sensitivity, providing new ideas for environmental monitoring and public health control.
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INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
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2024
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IF 7.7
Ting Wu,Huashan Sun,Wenyao Wang,Bin Xie,Zhengjie Wang,Jianqi Lu,Anming Xu,Weiliang Dong,Jie Zhou,Min Jiang
Enzymatic PET recycling has emerged as a promising green solution in addition to mechanical recycling, but low soluble expression levels of the inherently hydrophobic PET hydrolases hinder large-scale applications. Here, we propose a novel strategy for enhanced production of FastPETase in Escherichia coli using co-expression of molecular chaperones from Ideonella sakaiensis . Co-expression of cognate DnaK and DnaJ chaperones significantly increased soluble FastPETase expression (up to 2.5-fold), surpassing commercial chaperone plasmids. Furthermore, a combinatorial approach employing co-expression of DnaK/DnaJ chaperones and fusion of FastPETase with the VNp6-tag significantly boosted FastPETase secretion, yielding over 2 g/L of target protein in a 5-l bioreactor. Notably, the crude FastPETase in fermentation broth displayed comparable PET hydrolysis effects to the purified enzyme. This work not only provides new insights into the process of chaperones in protein folding but also suggests a novel and efficient strategy for producing recombinant proteins.
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Food Bioscience
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2024
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IF 4.8
Chenghui Zhang,Changzhu Li,Tariq Aziz,Metab Alharbi,Haiying Cui,Lin Lin
Food processing environments contaminated with E. coli O157 :H7 and forming biofilms will be a continuous source of contamination, leading to foodborne illness and food spoilage. Now, the main countermeasure is chemical disinfectants, but the use of disinfectants may cause the development of drug-resistant bacteria and other negative effects. Therefore, there is an urgent need to find novel antimicrobial agents. Quorum-sensing inhibitors (QSI) are a promising strategy to control biofilm formation. This study aimed to screen the optimal QSI of E. coli O157 :H7 from plant-derived small molecules by biofilm and QS inhibitory activities and to validate their effectiveness in combination with disinfectants. In addition, the inhibition mechanism of gallic acid on biofilm formation was further explored. Gallic acid was screened as the QSI of E. coli O157 :H7, and its AI-2 inhibitory activity against LuxS/AI-2 QS system reached 95.54% and 98.89% after treatment with 1/2 MIC gallic acid for 4 h and 6 h, respectively. It inhibited biofilm formation by affecting flagellar assembly, chemotaxis, and expression of adhesion factor-related genes, which interfered with the transition of bacteria from reversible to irreversible adhesion. In beef broth simulation system, the inhibition rate was greater than 90.00% in all gallic acid and benzalkonium chloride combination groups. Therefore, gallic acid can be a potential antimicrobial synergist in the food industry, combined with disinfectants to control E. coli O157 :H7 biofilms while avoiding the development of resistance.
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JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY
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2025
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IF 6.2
Qian Zhang,Xudong Lü,Yuanyuan Jin,Mengjia Tang,Miao Wang,Sen Zou,Shuai Fan,Zhaoyong Yang
Cyst(e)inase, an engineered human cystathionine-γ-lyase (hCGL), effectively degrades l-Cys and CSSC, inhibiting various tumors in vivo with minimal toxicity. However, its current activity and stability limit its clinical application. To enhance its therapeutic potential, we utilized folding free energy calculations and amino acid site conservation to identify 46 potential mutants. Among them, 17 mutants exhibited improved activity or stability, while six showed a loss of function. Notably, mutant L142E enhanced activity for both substrates, and E349S displayed 2.8 times higher activity toward CSSC and a 12.8 °C increase in Tm, despite reduced activity toward l-Cys. Saturation mutagenesis highlighted the importance of spatial constraints for substrate selectivity. MD simulations suggested that distal mutations stabilize the near-attack conformation, enhancing the activity. In vitro cytotoxicity assays confirmed that the mutants L142E and E349S significantly inhibited gastric and pancreatic cancer cells. This study provides valuable insights for improving therapeutic enzyme design.
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REACTIVE & FUNCTIONAL POLYMERS
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2024
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IF 4.5
Zheng Cao,Han Wu,Mengxiao Yang,Zhen Li,Xin Chen,Lin Liu
It is a high demand but a great challenge to construct all-in-one ionic conductive hydrogels with excellent mechanical performances, transparency, self-adhesion, conductivity and environmental tolerance. Herein, a versatile gel platform was developed via a facile and rapid photopolymerization of acrylic acid (AA) in deep eutectic solvent (DES) with multiple roles simultaneously as water-free solvent, ionic conductor , regulator of hydrogen bond density. Benefiting from the formed crosslinking networks including covalently cross-linked polymer network and multiple dynamic interactions, the resultant PAA-DES gels exhibited high stretchability of 884.7 ± 4.9%, toughness of 31.2 ± 1.4 MJ/m 3 , fatigue resistance and recovery ability, transparency of 93%, self-adhesive strength of 472 kPa. Moreover, the inherent advantages of DES enabled the gels with good ionic conductivity (2.5 ± 0.2 mS/cm), wide working window and biocompatibility . The PAA-DES as self-adhesive ionic sensors not only possessed wide strain range (∼400%) and stability, but also displayed excellent humidity (30–80%), temperature (−40–60 °C), and sweat tolerance which could precisely and steadily discern and monitor human motions and weak physiological signals. Thus, this work not only provides a strategy to construct all-in-one ionic conductive gels with high elasticity, fatigue resilience, transparency, self-adhesion and wide environmental tolerance, but also exploits versatile platform for intelligent gel sensor and e-skin.
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Molecular Catalysis
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2025
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IF 4.9
Bo Fan,Run Lin,Xinyu Gu,Ruibing Cui,Ruiqing Yang,Yu-Cai He
Alcohols can be extensively used in the production of fine chemicals, such as fuel additives, food supplements and pharmaceutical intermediates, which can be acquired by the reduction of biomass-derived aldehyde. In this study, the recombinant Escherichia coli KPADH was genetically constructed through the co-expression of alcohol dehydrogenase from Kluyveromyces polysporus and glucose dehydrogenase from Bacillus subtilis . Biomass-derived aldehydes were biologically converted into alcohols in a benign system. In deep eutectic solvent (DES) choline chloride:glycerol-H 2 O (choline chloride:glycerol, 10 wt %) containing E. coli KPADH cells (0.1 g/mL), HMF (50 mM), glucose (2 equivalents), and NAD + (0.1 μM/mM HMF), bioreduction of HMF into 2,5-bis(hydroxymethyl)furan was implemented, acquiring a high yield of 98.1 % within 8 h. Other biobased compounds, such as isovanillin, vanillin, p -hydroxybenzaldehyde, furfural, and benzaldehyde were also converted into their corresponding alcohols. According to the molecular docking results, HMF had the lowest CDOCKER energy value of -27.422 kcal/mol. It was found that HMF displayed strong binding affinity with E. coli KPADH, resulting in enhanced binding stability and superior catalytic reduction activity. This study demonstrated a green and highly effective biocatalytic method for the synthesis of biobased alcohols.
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ANALYTICAL CHEMISTRY
·
2020
·
IF 6.785
Xuan Sun,Yu Wang,Lu Zhang,Sha Liu,Man Zhang,Jiang Wang,Baoan Ning,Yuan Peng,Jing He,Yonggang Hu,Zhixian Gao
Escherichia coli O157:H7 has been reported as an important pathogenic bacteria causing serious infection and economic loss. However, detection of Escherichia coli O157:H7 needs improvement, given its current complexity and sensitivity. Herein, we attempt to build a fluorescence sensing method to detect Escherichia coli O157:H7 with easy operation and high efficiency. The target virulence gene sequences are recognized and cleaved by the CRISPR-Cas9 system, and trigger strand displacement amplification and rolling circle amplification. After amplification reactions, massive products can hybridize with the probes, the fluorescence of which are quenched based on a metal–organic framework platform, leading to the fluorescence recovery at typical excitation/emission wavelengths of 480/518 nm. This method exhibits high sensitivity with the detection limit at 4.0 × 101 CFU mL–1 and a wide range from 1.3 × 102 CFU mL–1 to 6.5 × 104 CFU mL–1. Meanwhile, this assay also shows significant specificity and applies to practical samples with high accuracy. Therefore, our method would have great potential application in bacterial detection, food safety monitoring, or clinical diagnostics.
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Frontiers in Microbiology
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2024
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IF 4
Song Zhenyan,He Jiawei,Yu Wenjing,He Chunxiang,Yang Miao,Li Ping,Li Ze,Jian Gonghui,Cheng Shaowu
Background: Schisanlactone E, also known as XueTongSu (XTS), is an active compound extracted from the traditional Tujia medicine Kadsura heteroclita (“XueTong”). Recent studies highlight its anti-inflammatory and antioxidant properties, yet the mechanisms of XTS’s therapeutic effects on Alzheimer’s disease (AD) are unclear. This study aims to elucidate the therapeutic efficacy and mechanisms of XTS in AD.Methods: Ten C57BL/6 mice were assigned to the control group (NC), and twenty APP/PS1 transgenic mice were randomly divided into the model group (M) (10 mice) and the XTS treatment group (Tre) (10 mice). After an acclimatization period of 7 days, intraperitoneal injections were administered over a 60-day treatment period. The NC and M groups received saline, while the Tre group received XTS at 2 mg/kg. Learning and memory abilities were assessed using the Morris Water Maze (MWM) test. Histopathological changes were evaluated using hematoxylin and eosin (HE) and Nissl staining, and immunofluorescence was used to assess pathological products and glial cell activation. Cytokine levels (IL-1β, IL-6, TNF-α) in the hippocampus were quantified by qPCR. 16S rDNA sequencing analyzed gut microbiota metabolic alterations, and metabolomic analysis was performed on cortical samples. The KEGG database was used to analyze the regulatory mechanisms of XTS in AD treatment.Results: XTS significantly improved learning and spatial memory in APP/PS1 mice and ameliorated histopathological changes, reducing Aβ plaque aggregation and glial cell activation. XTS decreased the expression of inflammatory cytokines IL-1β, IL-6, and TNF-α. It also enhanced gut microbiota diversity, notably increasing Akkermansia species, and modulated levels of metabolites such as isosakuranetin, 5-KETE, 4-methylcatechol, and sphinganine. Pathway analysis indicated that XTS regulated carbohydrate metabolism, neuroactive ligand-receptor interactions, and alanine, aspartate, and glutamate metabolism, mitigating gut microbiota dysbiosis and metabolic disturbances.Conclusion: XTS ameliorates cognitive deficits, pathological changes, and inflammatory responses in APP/PS1 mice. It significantly modulates the gut microbiota, particularly increasing Akkermansia abundance, and influences levels of key metabolites in both the gut and brain. These findings suggest that XTS exerts anti-AD effects through the microbial-gut-brain axis (MGBA).
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