Toxics
·
2025
·Vol. 13
·期 9
·706
·
IF 4.1
Juntong Gao,Qimeng Yang,Xiarui Fan,Xinwei Zhou,Peng Ren
Toxicological effects of microplastics (MPs) have been confirmed in a variety of microorganisms in aquatic environments, and they are closely correlated with the physicochemical properties of the MPs. In a natural environment, different aging treatments always induce different alterations in the physicochemical properties of MPs, thus influencing their environmental behaviors and biotoxicity. In this work, physicochemical properties and toxicity towardsEscherichia coli(E. coli) were investigated in polystyrene (PS) MPs (3 and 10 μm) before and after aging by UV irradiation and biofilm formation, respectively. The results show that UV irradiation and biofilm formation led to different alterations in the surface morphologies and functional groups of PS. The UV-aged 3 μm PS had the strongest inhibitory effect onE. coligrowth, and the bio-aged 10 μm PS had the strongest beneficial effect onE. coligrowth. Also, the ATPase activity, production of intercellular ROS, and MDA content of theE. coliwere affected differently. UV aging enhanced the toxicity of PS towardsE. coli, while bio-aging had an opposite weakening effect. Overall, our research verified the remarkable differences in the physicochemical properties and biotoxicity of PS induced by UV aging and bio-aging.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ANALYTICA CHIMICA ACTA
·
2025
·
IF 6
Ximei Zhang,Lanzhen He,Guangmin Zhang,Fenying Kong,Lanlan Chen
Background Escherichia coli ( E. coli ) is a model microorganism extensively used in microbial research due to its well-characterized physiology and genetic tractability. Monitoring its physiological indicators, such as metabolic activity and stress responses, is essential for understanding microbial life processes. However, existing methods often lack sensitivity, rapidity, and biocompatibility. This study addresses these limitations by combining electrochemiluminescence (ECL) biosensing with a biocompatible interface, to enable precise and efficient monitoring of E. coli 's physiological state. Results This study presents a novel ECL biosensor that leverages the biocompatibility of bovine serum albumin (BSA) with E. coli . The biosensor employs horseradish peroxidase (HRP) and 4-chloro-1-naphthol (4-CN) to induce a precipitation reaction that quenches the ECL signal of CdS–K 2 S 2 O 4 , enabling the sensitive detection of endogenous hydrogen peroxide (H 2 O 2 ) produced by E. coli . The sensor exhibits excellent linearity, stability, and reproducibility, with a detection limit of 54 nM for H 2 O 2 . Additionally, the biosensor effectively distinguishes between antibiotic-resistant and sensitive strains of E. coli , demonstrating its potential for comprehensive physiological assessment. Significance This innovative ECL biosensor represents a significant advancement in microbial monitoring, combining high sensitivity, rapidity, and biocompatibility, offering a powerful tool for comprehensive physiological monitoring in bioanalytical sciences. Its potential applications in biotechnology, food industry, and drug research highlight its practical relevance.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
MICROCHEMICAL JOURNAL
·
2025
·
IF 5.1
Yuanjian Liu,Yan Qi,Panpan Liu,Yusong Wan,Fengyang Wang,Yunlong Liu,Xiaohui Xiong
Herein, a novel bipolar electrode-electrochemiluminescence (BPE-ECL) biosensing strategy was developed, engineered to achieve highly and pathogen-specific detection of Escherichia coli O157:H7 ( E. coli O157:H7) through enzymatic cascade signal transduction. Crucially, this strategy employs β-galactosidase (β-gal) activity as a biomarker signature, wherein the enzymatic hydrolysis of p -nitrophenyl-β-D-galactopyranoside (PNPG) generates electroactive intermediates, p-nitrophenol (pNP). The pNP undergoes a six-electron reduction reaction at the closed BPE cathode electrode and simultaneously oxidizes phosphorus Ru(bpy) 3 2+ at the anode electrode to trigger obvious ECL signal. The ECL signal amplification of enzymatic substrates with mono-, bi-, and tetra-electronic systems is inherently constrained by inefficient electron transfer, resulting in suboptimal sensing performance. In contrast, the PNPG/pNP-based detection platform demonstrates superior sensing capabilities. For indirect quantification of E. coli O157:H7, the ECL intensity was linearly correlated with bacterial concentration. The optimized biosensor, through rigorous tuning of enzymatic catalysis and ECL signal amplification strategies, delivers a wide dynamic range (10(Zhang et al., 2023a 1) –10 6 CFU) and a low detection limit (LOD = 2 CFU) in 200 μL of bacterial samples. The real sample effect was evaluated, and the assay successfully detected E. coli O157:H7 in water, juice, and pure milk. This label-free platform integrates operational simplicity and high specificity, offering a promising solution for on-site monitoring of foodborne pathogens and clinical diagnostics.
✓ 已验证
产品关联
DOI
高影响因子
Frontiers in Immunology
·
2025
·
IF 5.9
DongXue Ma,YuXin Zhang,Jia Zhang,Jun Shi,ShanHu Gao,Fei Long,Xin Wang,XingYu Pu,Jiayao Sun,Shuang Liang,Richard D. Cannon,Silas Villas-Boas,Ting-Li Han
Introduction: Escherichia coli Nissle 1917 (EcN) is one of the most extensively studied nonpathogenic Gram-negative probiotic strains worldwide. Recent research has highlighted the ability of EcN outer membrane vesicles (OMVs) to enhance the phagocytosis and proliferation of RAW264.7 macrophages. However, the impact of EcN-OMVs on M1/M2 polarization and metabolic modulation remains unknown.Methods: In this study, we evaluated the metabolic effects of EcN-OMVs on RAW264.7 macrophage polarization using metabolomic, transcriptomic, and fluxomic approaches.Reuslts: We found that the RAW264.7 macrophages phagocytosed EcN-OMVs, triggering upregulation of the HIF-1, mTORC1, and NF-κB signaling pathways. This metabolic reprogramming enhanced glycolysis, suppressed the TCA cycle, elevated intracellular reactive oxygen species (ROS), TNF-α, IL-6, IL-1β, ATP, and nitric oxide (NO) production, and promoted macrophage proliferation, migration, invasion, and M1-type polarization.Discussion: In summary, this research establishes a theoretical foundation for utilizing probiotic OMVs in immunomodulatory therapeutic applications.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2025
·
IF 9.7
Xingxing Lv,Jing Sun,Zixia Li,Fang Guo,Jing Liu,Danqing Liu,Zhimin Tian,Liangcan He,Yongquan Qu,Shaoqin Liu
The biohybrid-mediated semi-artificial photosynthetic system ingeniously combines the superior light-trapping characteristics of photosensitizers with the highly efficient catalytic capabilities of biocatalysts. However, the slow transfer of electrons at the micro-interface between the photosensitizer and biocatalyst is challenging for the performance of semi-artificial photosynthetic systems. Here, we report a semi-artificial photosynthetic biohybrid system comprising the positively charged hybrids of copper quantum dots/Mxenes encapsulated inside conducting polymer polypyrrole (Cu-MXene-PPY) and negatively charged Escherichia coli ( E. coli ) via electrostatic interaction. This system achieved an ideal state, wherein the photosensitizer possesses strong light absorption capability and a positive surface charge, enabling efficient electron transfer with E. coli . The semi-artificial photosynthetic system delivered a high catalytic performance for hydrogen production, with a yield of 2.37 mmol of hydrogen in 5 h (420–780 nm, 2000 W/m 2 ). The mechanistic investigation of the catalysis indicated that the E. coli /Cu-MXenes-PPY biohybrids enabled inhibition of lactate production coupled with acceleration of formic acid production in bacteria under the influence of photoelectrons, which facilitated H + reduction and H 2 production. Overall, this approach enables the construction of a robust semi-artificial photosynthetic system for H 2 production.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
LWT-FOOD SCIENCE AND TECHNOLOGY
·
2020
·
IF 4.006
Maomao Ma,Junxin Zhao,Zheling Zeng,Dongman Wan,Ping Yu,Ding Cheng,Deming Gong,Shuguang Deng
In this study, the antibacterial activity of monocaprin against Gram-negative foodborne pathogens and its underlying mechanism against E. coli were investigated. It was found that monocaprin exerted excellent antibacterial effects on E. coli , Vibrio parahaemolyticus and Shigella dysenteriae with the minimum inhibitory concentration/minimum bactericidal concentration values of 1.25 mM, 0.625 mM and 0.625 mM, respectively. The results of growth curve and time-kill assay showed that monocaprin could not only delay the growth of E. coli , but quickly inactivate the cells within 15 min. The effects of monocaprin on membrane integrity, inner and outer membrane permeability, proton motive force, and its interaction with model membranes and cell morphology were investigated to explore the antibacterial mechanism of monocaprin. The results indicated that monocaprin rapidly inactivated E. coli by penetrating its outer membrane, then destroying the phospholipid bilayer structure of the inner membrane, as well as dissipating the proton motive force, resulting in increases of the permeability of the outer and inner membranes and leakage of intracellular substances. Besides, monocaprin significantly reduced the viability of E. coli in apple and carrot juices at 4 °C and 25 °C without changing their sensory properties .
✓ 已验证
DOI
高影响因子
BIOTECHNOLOGY AND BIOENGINEERING
·
2024
·Vol. 122
·期 3
·724-735
·
IF 3.5
Xia Ke,Hong-Duo Dong,Xi-Man Zhao,Xin-Xin Wang,Zhi-Qiang Liu,Yu-Guo Zheng
C14-functionalized steroids enabled diverse biological activities in anti-gonadotropin and anticancer therapy. However, access to C14-functionalized steroids was impeded by the deficiency of chemical synthetic methods. Recently, several membrane-bound fungal cytochrome P450s (CYPs) have been identified with steroid C14α-hydroxylation activity. However, the lack of efficient heterologous overexpression strategy hampered their further characterization and molecular engineering. In the present study, sequences of fungi-derived CYP genes encoding putative 14α-hydroxylase were selected and bioinformatically analyzed. Substitution of the N-terminal hydrophobic helix by a soluble maltose binding protein tag significantly enhanced the soluble expression level in Escherichia coli . A novel CYP originated from Bipolaris oryzae was discovered with high steroidal C14α-hydroxylation activity when coupled with the redox partner CPR lun . A catalytically self-sufficient chimeric CYP-CPR was built by intramolecular fusion, and the electronic transfer rate was improved. A coenzyme NADPH regeneration system was finally constructed by the co-expression of glucose dehydrogenase. The developed soluble multi-enzyme cascade biotransformation system supported the selective C14α-hydroxylation toward progesterone with a final titer of 34.54 mg/L, the highest level achieved in E. coli -based heterologous expression system. This study provides insightful ideas on the functional expression of fungi-derived CYPs and promises an efficient C14α-hydroxylation system for steroidal drugs through protein engineering.
✓ 已验证
DOI
高影响因子
Environmental Science-Nano
·
2025
·
IF 5.1
Ying Wang,Fuming Wang,Xuyang Feng,Haoyou Jiang,Hualin Zhang,Yongfang Qian,Botian Zhu,Yaping Huang,Yimin Zhu
In recent years, microbial pollution has become a serious environmental problem, and the release of microorganisms into the water environment seriously threatens human health. As environment-friendly and low-cost antibacterial agents, Mg(OH)2 nanoparticles (M-NPs) have garnered considerable attention for their small size, innocuity, no drug resistance, chemical stability and thermal stability. However, little is known about the physiological changes that bacteria undergo in the presence of M-NPs. In this work, the antibacterial mechanism of M-NPs synthesized by applying the coprecipitation method was investigated using Escherichia coli (E. coli) as a model system. The oxygen vacancies on the M-NP surface, which can produce reactive oxygen species (ROS, ·O2−, H2O2, and ·OH), were examined via O2-temperature programmed desorption (O2-TPD). Abnormality in three central metabolic pathways (energy, glucose and tricarboxylic acid cycle) induced by M-NPs was detected by analyzing the activity of respiratory chain dehydrogenase, gluconokinase (GK) and succinate dehydrogenase (SDH). The downregulated activity and gene expression levels of GK confirmed that M-NPs play an inhibitory role, and these physiological changes result in cell death. Thus, M-NPs have great potential in the field of preventing and controlling microbial pollution.
✓ 已验证
产品关联
DOI
高影响因子
PROCESS BIOCHEMISTRY
·
2013
·
IF 2.414
Xiaolin Pei,Hongyu Zhang,Lijun Meng,Gang Xu,Lirong Yang,Jianping Wu
A nitrile hydratase (NHase) gene from Aurantimonas manganoxydans was cloned and expressed in Escherichia coli BL21 (DE3). A downstream gene adjacent to the β-subunit was necessary for the functional expression of the recombinant NHase. The structural gene order of the Co-type NHase was α-subunit beyond β-subunit, different from the order typically reported for Co-type NHase genes. The NHase exhibited adequate thermal stability, with a half-life of 1.5 h at 50 °C. The NHase efficiently hydrated 3-cyanopyridine to produce nicotinamide. In a 1-L reaction mixture, 3.6 mol of 3-cyanopyridine was completely converted to nicotinamide in four feedings, exhibiting a productivity of 187 g nicotinamide/g dry cell weight/h. An industrial auto-induction medium was applied to produce the recombinant NHase in 10-L fermenter. A glycerol-limited feeding method was performed, and a final activity of 2170 U/mL culture was achieved. These results suggested that the recombinant NHase was efficiently cloned and produced in E. coli .
✓ 已验证
DOI
高影响因子
ELECTRONIC JOURNAL OF BIOTECHNOLOGY
·
2020
·
IF 2.894
Longxing Wang,Wenjun Zhu,Zhen Gao,Hua Zhou,Fei Cao,Min Jiang,Yan Li,Honghua Jia,Ping Wei
Background L- tert -Leucine has been widely used in pharmaceutical, chemical, and other industries as a vital chiral intermediate. Compared with chemical methods, enzymatic methods to produce L- tert -leucine have unparalleled advantages. Previously, we found a novel leucine dehydrogenase from the halophilic thermophile Laceyella sacchari ( Ls LeuDH) that showed good thermostability and great potential for the synthesis of L- tert -leucine in the preliminary study. Hence, we manage to use the Ls LeuDH coupling with a formate dehydrogenase from Candida boidinii ( Cb FDH) in the biosynthesis of L- tert -leucine through reductive amination in the present study. Result The double-plasmid recombinant strain exhibited higher conversion than the single-plasmid recombinant strain when resting cells cultivated in shake flask for 22 h were used. Under the optimized conditions, the double-plasmid recombinant E. coli BL21 (pETDute-FDH-LDH, pACYCDute-FDH) transformed 1 mol·L -1 trimethylpyruvate (TMP) completely into L- tert -leucine with greater than 99.9% ee within 8 h. Conclusions The Ls LeuDH showed great ability to biosynthesize L- tert -leucine. In addition, it provided a new option for the biosynthesis of L- tert -leucine. How to cite Wang L, Zhu W, Gao Z, et al. Biosynthetic L- tert -leucine using Escherichia coli co-expressing a novel NADH-dependent leucine dehydrogenase and a formate dehydrogenase. Electron J Biotechnol 2020;47. https://doi.org/10.1016/j.ejbt.2020.07.001
✓ 已验证
DOI
高影响因子
BIORESOURCE TECHNOLOGY
·
2018
·
IF 5.807
Daniela Parra-Ramírez,Alfredo Martinez,Carlos Ariel Cardona
In this work, d -lactic acid production was evaluated from a simulated hydrolysate of corn stover (32 g/L xylose, 42 g/L glucose) with the metabolically engineered Escherichia coli strain JU15. Based on the experimental results, a technical and economic analysis of the entire process was performed using the Aspen Plus software. As a result, it was possible to show that the strain can efficiently produce lactic acid from both sugars, reaching a final concentration of 40 g/L and a yield of 0.6 g lactic acid/g sugars. The process is economically viable at higher scales of 1000 tons/day. The cost distribution is influenced by the scale of the process; on a larger scale, the cost of raw materials represents a higher percentage of total cost than it does on smaller scales. The use of a metabolically engineered strain allows a better use of the sugars obtained from agroindustrial residues.
✓ 已验证
DOI
PubMed
高影响因子
NEW JOURNAL OF CHEMISTRY
·
2022
·Vol. 46
·期 13
·5939-5947
·
IF 3.925
Xin Sun,Hongai Zheng,Shuangyan Jiang,Meilin Zhu,Yao Zhou,Derui Wang,Yankun Fan,Lili Hu,Daquan Zhang,Lizhi Zhang
The sulfate radical-based advanced oxidation processes (SR-AOPs) are well-established and efficient techniques for the degradation of organic pollutants. Fe2+ is used as an environmentally friendly and cost-effective catalyst for activating peroxymonosulfate (PMS) to generate sulfate radicals (SO4−˙). In some past studies, the slow process of reducing Fe3+ to Fe2+ reduced the overall reaction rate of the SR-AOP system. To overcome this challenge, in this work, we for the first time fabricated a new composite activator, FeOCl decorated by graphene quantum dots (GQDs), by a facile method for activating PMS. The experimental results demonstrate that the as-prepared FeOCl/GQD catalysts can efficiently degrade organic pollutants and kill Escherichia coli through activating PMS to generate active species. Notably, the FeOCl/(16.7 wt%) GQD composite can activate PMS to degrade organics (97.8% of RhB within 30 min) and inactivate E. coli (99.1% within 10 min) with a pH range from 3 to 11. Moreover, mechanism analyses showed that the active species were SO4−˙, ˙OH, 1O2 and O2−˙ in the FeOCl/(16.7 wt%) GQDs + PMS system, and SO4−˙ and 1O2 were proved to be the main active species. The addition of GQDs promoted the reduction of Fe3+ to Fe2+, thereby accelerating the degradation rate. Our study suggests that the promising strategy of exploiting highly efficient AOP platforms has many applications.
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）