FOOD CHEMISTRY
·
2018
·
IF 4.946
Chun Wang,Keyu Xing,Ganggang Zhang,Meifang Yuan,Shaolan Xu,Daofeng Liu,Wenyao Chen,Juan Peng,Song Hu,Wei-Hua Lai
Escherichia coli O157:H7 ( E. coli O157:H7) is a potential threat to human health; thus, a rapid and sensitive method for detecting it is necessary. We designed a single-stranded DNA that contained an appended block and anchoring block. The appended block acted as a scaffold to prepare fluorescent Ag nanoclusters (AgNCs). The anchoring block contained Poly A, which bound with the surface of gold nanoparticles to quench the fluorescence of AgNCs. An interesting ELISA approach for detecting E. coli O157:H7 was established via fluorescent quenching of DNA-stabilized AgNCs by using a sandwich complex. The changes in fluorescence intensity of AgNCs were used to quantitatively detect E. coli O157:H7. The sensitivity for detecting E. coli O157:H7 reached 1.905 × 10 3 CFU/mL with a good linear range. Compared with conventional ELISA, the sensitivity of this technique increased by 30-fold. Moreover, this method demonstrated specificity and reproducibility and could be used in food samples.
研究领域:
生物技术
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分析化学
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微生物学
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食品科学
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产品关联
DOI
PubMed
高影响因子
MICROCHEMICAL JOURNAL
·
2025
·
IF 5.1
Jiayi Zhang,Zichun Song,Jiuying Cui,Wenbo Li,Song Huang,Bo Ling,Kai Zhang,Xianjiu Liao,Jihua Wei
The human gastrointestinal system contains the conditional pathogen Escherichia coli ( E. coli ), which is a significant cause of vomiting and diarrhea—both of which can be fatal in extreme cases. Given the surge in hospital infections and water pollution, the development of early detection and diagnosis procedures is imperative. This study proposes an electrochemical biosensor for E. coli detection, utilizing nucleic acid aptamers as recognition elements and using E. coli-2571 as an example. It is based on the CRISPR/Cas gene-editing technology. Specifically, the collateral cleavage activity of Cas12a shifts the electrochemical signal after loading the DNA sequence tagged with an electrochemical signal onto the gold electrode, which ultimately enables the identification of E. coli . The biosensor has a detection limit of 13.1 CFU/mL and exhibits a good linear relationship in the concentration range of 10 2 ––10 7 CFU/mL. It was effectively used for the quantitative detection of E. coli in milk and pure water, with a recovery rate ranging from 93.12 % to 98.93 %. The biosensor offers a rapid, precise, affordable, and sensitive tool for E. coli detection. It is anticipated to become a powerful instrument for identifying microorganisms that pose a risk to public health and human health.
研究领域:
分子生物学
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微生物学
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生物传感技术
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公共健康
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产品关联
DOI
高影响因子
Frontiers in Chemistry
·
2022
·
IF 5.545
Wang Huan,Fan Yanmiao,Yang Qiaoli,Sun Xiaoyu,Liu Hao,Chen Wei,Aziz Ayesha,Wang Shenqi
Redox activity is an important indicator for evaluating electrochemical biosensors. In this work, we have successfully polymerized indole-5-carboxylic acid into poly-5-carboxyindole nanomaterials (PI-5-CA), using its superior redox activity, and introduced carboxylated single-walled carbon nanotubes (C-SWCNTs) to synthesize a composite material. Finally, a synthesized composite material was used for the modification of the glass carbon electrode to fabricate the PI-5-CA/C-SWCNTs/GCE-based immunosensor and was successfully applied for the sensitive detection of E. coli O157:H7. The fabricated immunosensor exhibited an outstanding electrocatalytic activity toward the detection of E. coli O157:H7 with a remarkably lowest limit of detection (2.5 CFU/ml, LOD = 3 SD/k, n = 3) and has a wide linear range from 2.98×101 to 2.98×107 CFU/ml. Inspired from the excellent results, the fabricated electrode was applied for the detection of bacteria from real samples (water samples) with a good recovery rate (98.13–107.69%) as well as an excellent stability and specificity. Owing to its simple preparation, excellent performance, and detection time within 30 min, our proposed immunosensor will open a new horizon in different fields for the sensitive detection of bacteria from real samples.
研究领域:
生物传感
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材料科学
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微生物学
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产品关联
DOI
PubMed
高影响因子
STAR Protocols
·
2023
·
IF 0
Zhen-Ping Zou,Yu-Hang Fan,Yue Du,Ting-Ting Fang,Wei Du,Ying Zhou,Bang-Ce Ye
Summary Engineered microorganisms hold potential for disease diagnosis and treatment. Here, we present a protocol to engineer E. coli Nissle 1917 strain (iROBOT) using genome insertion and plasmid construction to diagnose, record, and ameliorate inflammatory bowel disease in mice. We describe steps for constructing and administering iROBOT, diagnosing and recording colitis, preparing samples, and analyzing fluorescence and base editing ratios of iROBOT. We detail a colitis ameliorating assay using the disease activity index, colon length, tissue pathological section, and cytokine analysis. For complete details of the use and execution of this protocol, please refer to Zou et al. 1
研究领域:
微生物学
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分子生物学
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基因工程
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炎症性肠病
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DOI
PubMed
PROTEIN EXPRESSION AND PURIFICATION
·
2025
·
IF 1.2
Hao Wang,Xiaohui Zhang,Cunlong Yin,Lu Liu,Liang Chen,Hengfang Tang,Bo Wu,Junfeng Wang
Tumor necrosis factor receptor superfamily member 4 (OX40) is essential for the activation and maintenance of T cell immune function because of its recognition and regulation in signal transduction, therefore understanding the structure and dynamics of the membrane protein OX40 in a near-native membrane environment is critical for elucidating its functions. However, efforts to prepare OX40 in a stable, functional form and reconstitute it into a membrane-mimicking lipid system face persistent challenges, limiting progress in its structural and functional characterization. Here, we developed an efficient method for the expression in E. coli and purification of the N-terminal truncated transmembrane and cytoplasmic domains of OX40 (OX40-TC) using a TrpLE fusion system. High-purity OX40-TC was achieved and successfully reconstituted into membrane scaffold protein (MSP)-nanodiscs for the first time. Characterization through size-exclusion chromatography, dynamic light scattering, and transmission electron microscopy confirmed their stability and homogeneity. This study provides a reliable platform for investigating the structure and function of OX40-TC, advancing our understanding of OX40-mediated signaling and its therapeutic potential.
研究领域:
免疫学
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结构生物学
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分子生物学
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF SOL-GEL SCIENCE AND TECHNOLOGY
·
2018
·Vol. 88
·期 3
·654-659
·
IF 1.745
Wang Lijuan,Lv Hua,Li Binjie,Zhao Yanbao,Sun Lei
Flower-like ceria (CeO 2 ) architectures consisting of well aligned nanosheets were first synthesized by a glycol solvothermal method. The size of CeO 2 architectures is about 5 μm in width and 10 μm in length, with the nanosheets thickness below 100 nm. Subsequently, the adsorbed Ag ions on the surface of CeO 2 were in situ reduced to form Ag nanoparticles (NPs), leading to the fabrication of Ag/CeO 2 hybrid architectures (HAs). The formed Ag NPs with sizes of 20–40 nm were uniformly loaded on the surface of the CeO 2 sheets. The antibacterial properties of Ag/CeO 2 HAs against Gram-negative E. coli and Gram-positive S. aureus were evaluated by minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), and a filter paper inhibition zone method. The results demonstrated that Ag/CeO 2 HAs displayed excellent antibacterial activity toward S. aureus and E. coli , which were attributed to the synergistic antibacterial effect between Ag NPs and CeO 2 in HAs . Here, CeO 2 nanoflowers as a new substrate could restrict Ag NPs aggregations and improve their antibacterial activities. Therefore, the resulted Ag/CeO 2 HAs would be considered as a promising antibacterial agent.
研究领域:
材料科学
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微生物学
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产品关联
DOI
高影响因子
COLLOIDS AND SURFACES B-BIOINTERFACES
·
2019
·
IF 3.973
Lingyan Yang,Liliang Chen,Yi-Chun Chen,Lei Kang,Jiantao Yu,Yuhang Wang,Chengjia Lu,Tsutomu Mashimo,Akira Yoshiasa,Chia-Hua Lin
Immiscible bimetallic Ag–Cu system has been synthesized by the pulsed plasma in liquid method with a graph of one pulse duration. Herein, by combining X-ray power diffraction, K-edge X-ray absorption near edge structure and high-resolution transmission electron microscopy, our results indicate that homogeneously alloyed Ag–Cu nanoparticles (Ag–Cu NAs) have the average diameter about 2.1 nm, composed by 48.5 at% Ag and 51.5 at% Cu with chemical analysis and the estimated lattice parameter was 3.873 Å. The antibacterial property of Ag–Cu NAs was detected against E. coli and S. aureus strains according to the colony formed abilities of bacteria on agar plates covered with the nanoparticles. With very short incubation period, Ag–Cu NAs completely inhibited the E. coli and S. aureus growth at an ultralow concentration. The mechanism of antibacterial property of Ag–Cu NAs was performed by the inductively coupled plasma-atomic emission spectrometry and the plane wave pseudopotential method implemented in the CASTEP package based on the density functional theory. The Ag + dissolution is correlated with antibacterial activity for Ag–Cu NAs-assisted antibacterial treatment. These findings obtained revealed that our Ag–Cu NAs could be served as a containing material of numerous bacteria-free products in order to avoid their bacterial contamination.
研究领域:
材料科学
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微生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
NEW JOURNAL OF CHEMISTRY
·
2016
·Vol. 40
·期 7
·6332-6339
·
IF 3.277
Ren Liu,Huiwen Ge,Xue Wang,Jing Luo,Zhiquan Li,Xiaoya Liu
In this paper, a facile, economical and environmentally friendly synthetic method was developed to fabricate a Ag nanoparticle (NP) decorated graphene (GR/TA/Ag) composite with tannic acid (TA) as a reducing agent and stabilizing agent. The GR/TA/Ag composite was fully characterized using Fourier transform infrared spectroscopy (FTIR), ultraviolet-visible absorption spectroscopy (UV-vis), Raman spectroscopy, and X-ray photoelectron spectroscopy (XPS). Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) demonstrated that Ag NPs with diameters of up to 6 nm were homogeneously and uniformly deposited on graphene sheets. With an increasing concentration of AgNO3 used for immersion, the amount of Ag NPs loaded kept increasing without aggregation or deformation. The antibacterial properties of the GR/TA/Ag composite were studied using Gram-negative E. coli ATCC 25922 and Gram-positive S. aureus ATCC 6538 via both the disk diffusion method and the shaking flask method. The disk diffusion method results showed that the synthesized GR/TA/Ag composite had great release antibacterial properties owing to the loading of Ag NPs. In addition, the presence of TA gave the composite good non-release antibacterial properties, based on the results of the shaking flask method. The ingenious combination of the release-killing capabilities of Ag NPs and the contact-killing capabilities of TA bestow two-level antibacterial activity on the GR/TA/Ag composite, promoting the GR/TA/Ag composite as part of a new generation of powerful antibacterial agents with promising applications.
研究领域:
材料科学
·
微生物学
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产品关联
DOI
高影响因子
ENZYME AND MICROBIAL TECHNOLOGY
·
2024
·
IF 3.4
Jiehu Liu,Runtian Huo,Huixian Fu,Shiheng Chen,Xueyi Qiao,Bo Xu,Zhaoyuan Zhang,Jing Wu,Lingqia Su
β-nicotinamide mononucleotide (β-NMN) is a key precursor of nicotinamide adenine dinucleotide, and becomes attractive in the nutrition and health care fields, but its enzymatic synthesis is expensive. In this study, a six-enzyme cascade catalytic system was constructed to produce β-NMN. Using D-ribose and nicotinamide as substrates, the β-NMN yield reached 97.5 % catalyzed by purified enzymes. Then, after knocking out the genes encoding proteins that consume β-NMN in E. coli BL21(DE3), the similar β-NMN yield, 97.2 %, using the crude enzymes could be also obtained. After that, β-NMN synthesis was performed under increased substrate concentration, and 'modular' crude enzymes cascade catalytic reaction system was proposed to reduce the inhibition of polyphosphate on ribose-phosphate diphosphokinase activity, and the β-NMN yield reached 78.4 % at 10 mM D-ribose, which is 1.82 times of that in 'one-pot' reaction and represents the highest β-NMN preparation level with phosphoribosylpyrophosphate as the core reported till now.
研究领域:
生物化学
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合成生物学
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分子生物学
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产品关联
DOI
PubMed
高影响因子
CHEMICAL RESEARCH IN CHINESE UNIVERSITIES
·
2015
·Vol. 31
·期 1
·160-166
·
IF 0.875
Zuo Huajiang,Wen Wanhua,Wu Dingcai,Fu Ruowen,Tang Chunyi
Copolymers of quaternary ammonium monomer(QAM) and hydrophilic co-monomer were successfully synthesized by free radical polymerization. It was discovered that the hydrophilic co-monomers with poor antibacterial activity significantly enhanced the activity of QAM substituted with a long alkyl chain[ i.e. , N , N -dimethyl- N -dodecyl methacrylate ammonium bromide(DMAEMA-DB)]. When a suitable molar ratio of DMAEMA-DB to co-monomer was selected, the activity of the copolymers was up to 123 times that of the homopolymer of DMAEMA-DB against S. aureus , and 282 times that of it against E. coli . But unlike DMAEMA-DB, the co-monomers might weaken the activity of QAM substituted with a short alkyl chain[ i.e. , N , N -dimethyl- N -butyl methacrylate ammonium bromide(DMAEMA-BB)]. Moreover, it was found that copolymers of DMAEMA-DB were much more biocidal than those of DMAEMA-BB. Therefore, it could be speculated that the long alkyl chain plays an important role in the antibacterial activity, and that the hydrophilic co-monomers are beneficial to polymeric guaternary ammonium compounds(PQACs) to exert the positive effect of the long alkyl chain to the greatest degree.
研究领域:
高分子化学
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微生物学
·
材料科学
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产品关联
DOI
高影响因子
Chemical Science
·
2018
·Vol. 10
·期 5
·1351-1359
·
IF 9.063
Zhongju Ye,Hua Liu,Fuyan Wang,Xin Wang,Lin Wei,Lehui Xiao
It has been demonstrated that rod-shaped particles can achieve a high translocation efficiency for gene and drug delivery in biological samples. Previous theoretical calculations also confirmed that rod-shaped particles display higher diffusivity than their spherical counterparts in biological porous media. Understanding the diffusion dynamics of biological and non-biological rod-shaped particles in biological solutions as well as close to the lipid membrane is therefore fundamentally significant for the rational design of efficient cargos. With dark-field optical microscopy, the translational and three-dimensional (3D) orientational diffusion dynamics of individual rod-shaped particles (i.e., E. coli and upconversion microrods, UCMRs) in phosphate buffered saline (PBS) and on the lipid membrane are tracked at the single-particle level. In the buffer solution, faster rotation of E. coli in the z direction was observed even though its dynamics in the x–y plane is comparable with that of UCMRs. Interestingly, on the lipid membrane, distinct from the confined motion of UCMRs, anomalous rocking diffusion was observed, which might facilitate the subsequent survey of stronger association sites on the two-dimensional (2D) surface. These results would afford deep insight into the better understanding of the translocation mechanism by using rod-shaped particles as a delivery cargo in biological samples.
研究领域:
生物物理学
·
药物递送
·
细胞生物学
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产品关联
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2025
·
IF 13.2
Yuanzi Wu,Kaiqiang Zhou,Wenhui Li,Min Huan,Zhichao Yu,Fen Yan,Huixiao Hong,Dianping Tang,Yansong Guo,Zuquan Weng
The rise of antibiotic-resistant bacteria poses a serious global health threat, highlighting the urgent need for novel strategies beyond conventional antibiotic therapies. This study explores the potential of microbe-imprinted polymers (MIPs) as innovative, pathogen-specific affinity agents. Utilizing microbial surface-initiated polymerization, MIPs are in-situ synthesized on the surface of target microbes, creating flexible heteropolymers that precisely replicate microbial surface structures. This method exhibits high affinity ( K D = 2.7×10 8 CFU/mL for E. coli ) and selectivity at the strain level. MIPs offer significant advantages over traditional antibodies, including greater stability, cost-effectiveness, and a broader spectrum of binding capabilities, making them effective for identifying and targeting various microbial strains, including unidentified or drug-resistant variants. Moreover, their favorable biocompatibility and functional resilience in diverse environments position MIPs as promising candidates for rapid pathogen detection and therapeutic applications. This research paves the way for advanced biomimetic materials in microbe-specific diagnostics and combating infections, addressing the critical need for effective tools in antibiotic resistance surveillance.
研究领域:
生物材料学
·
微生物学
·
医学诊断
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产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）