Journal of Advanced Research
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2023
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IF 10.7
Zebin Weng,Fei Zeng,Minxin Wang,Sheng Guo,Zhijuan Tang,Kiyoshi Itagaki,Yajuan Lin,Xinchun Shen,Yaqi Cao,Jin-ao Duan,Fang Wang
Introduction The continuous emergence and rapid spread of multidrug-resistant bacteria have accelerated the demand for the discovery of alternative antibiotics. Natural plants contain a variety of antibacterial components, which is an important source for the discovery of antimicrobial agents. Objective To explore the antimicrobial activities and related mechanisms of two lavandulylated flavonoids, sophoraflavanone G and kurarinon in Sophora flavescens against methicillin-resistant Staphylococcus aureus . Methods The effects of sophoraflavanone G and kurarinone on methicillin-resistant Staphylococcus aureus were comprehensively investigated by a combination of proteomics and metabolomics studies. Bacterial morphology was observed by scanning electron microscopy. Membrane fluidity, membrane potential, and membrane integrity were determined using the fluorescent probes Laurdan, DiSC3(5), and propidium iodide, respectively. Adenosine triphosphate and reactive oxygen species levels were determined using the adenosine triphosphate kit and reactive oxygen species kit, respectively. The affinity activity of sophoraflavanone G to the cell membrane was determined by isothermal titration calorimetry assays. Results Sophoraflavanone G and kurarinone showed significant antibacterial activity and anti-multidrug resistance properties. Mechanistic studies mainly showed that they could target the bacterial membrane and cause the destruction of the membrane integrity and biosynthesis. They could inhibit cell wall synthesis, induce hydrolysis and prevent bacteria from synthesizing biofilms. In addition, they can interfere with the energy metabolism of methicillin-resistant Staphylococcus aureus and disrupt the normal physiological activities of the bacteria. In vivo studies have shown that they can significantly improve wound infection and promote wound healing. Conclusion Kurarinone and sophoraflavanone G showed promising antimicrobial properties against methicillin-resistant Staphylococcus aureus , suggesting that they may be potential candidates for the development of new antibiotic agents against multidrug-resistant bacteria.
研究领域:
药理学
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微生物学
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植物科学
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生物技术
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PubMed
高影响因子
MICROCHEMICAL JOURNAL
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2023
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IF 4.8
Xianfeng Wang,Chengxiang Chu,Yuanyi Deng,Yi Ma,Mei Yang,Huibo Luo,Danqun Huo,Changjun Hou
Accurate identification of Staphylococcus aureus ( S. aureus ) is crucial for food safety and clinical diagnosis. Particularly, identifying drug-resistant strains guides effective treatment and prevention of infectious diseases. Herein, we presented a highly efficient programmable CRISPR/Cas12a system for identification of methicillin-resistant S. aureus (MRSA). Genus-specific gene (spec gene) and methicillin-resistant gene (mecA gene) of S. aureus were amplified by PCR. According to the sequences of spec gene and mecA gene, corresponding programmable crRNAs were designed and prepared to construct CRISPR/Cas12a system, which recognized and bound to the PCR products through complementary interactions to activate the trans -cleavage activity of Cas12a. This led to the indiscriminate digestion of surrounding FQ-reporter, releasing a distinct fluorescence signal for MRSA identification. In addition, we devised a pair of AuNPs-DNA probes for colorimetric recognition of S. aureus . Target-triggered trans -cleavage for linker probe led to an non-aggregation of AuNPs-DNA probes pair. This led to a noticeable appearance of red color, enabling naked-eye detection. Thus, MRSA identification was realized with remarkable sensitivity and exceptional selectivity. Successful identification of MRSA in clinical samples validated the practical applications of the proposed CRISPR/Cas12a assay, establishing it as a universal platform for diagnosing pathogenic microorganisms with versatility and compatibility.
研究领域:
分子生物学
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医学诊断
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食品安全
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DOI
高影响因子
Jove-Journal of Visualized Experiments
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2023
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IF 1.2
Xiaoqiang Zeng,Hongwu Sun,Yan Ye,Xing Luo,Dingyi Cai,Yun Yang,Ting Chen,Cun Sun,Shaotong Zhang,Hao Zeng
Nanoemulsion adjuvant vaccines have attracted extensive attention because of their small particle size, high thermal stability, and ability to induce validly immune responses. However, establishing a series of comprehensive protocols to evaluate the immune response of a novel nanoemulsion adjuvant vaccine is vital. Therefore, this article features a rigorous procedure to determine the physicochemical characteristics of a vaccine (by transmission electron microscopy [TEM], atomic force microscopy [AFM], and dynamic light scattering [DLS]), the stability of the vaccine antigen and system (by a high-speed centrifuge test, a thermodynamic stability test, SDS-PAGE, and western blot), and the specific immune response (IgG1, IgG2a, and IgG2b). Using this approach, researchers can evaluate accurately the protective effect of a novel nanoemulsion adjuvant vaccine in a lethal MRSA252 mouse model. With these protocols, the most promising nanoemulsion vaccine adjuvant in terms of effective adjuvant potential can be identified. In addition, the methods can help optimize novel vaccines for future development.
研究领域:
疫苗学
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免疫学
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微生物学
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药学
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DOI
PubMed
高影响因子
Foods
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2023
·Vol. 12
·期 23
·4208
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IF 5.2
Mao-Cheng Sun,Dian-Dian Li,Yu-Xin Chen,Xiu-Juan Fan,Yu Gao,Haiqing Ye,Tiehua Zhang,Changhui Zhao
Reuterin is a dynamic small-molecule complex produced through glycerol fermentation byLimosilactobacillus reuteriand has potential as a food biopreservative. Despite its broad-spectrum antimicrobial activity, the underlying mechanism of action of reuterin is still elusive. The present paper aimed to explore the antibacterial mechanism of reuterin and its effects on membrane damage and the intracellular metabolome ofS. aureus. Our results showed that reuterin has a minimum inhibitory concentration of 18.25 mM againstS. aureus, based on the 3-hydroxypropionaldehyde level. Key indicators such as extracellular electrical conductivity, membrane potential and permeability were significantly increased, while intracellular pH, ATP and DNA were markedly decreased, implying that reuterin causes a disruption to the structure of the cell membrane. The morphological damage to the cells was confirmed by scanning electron microscopy. Subsequent metabolomic analysis identified significant alterations in metabolites primarily involved in lipid, amino acid, carbohydrate metabolism and phosphotransferase system, which is crucial for cell membrane regulation and energy supply. Consequently, these findings indicated that the antibacterial mechanism of reuterin initially targets lipid and amino acid metabolism, leading to cell membrane damage, which subsequently results in energy metabolism disorder and, ultimately, cell death. This paper offers innovative perspectives on the antibacterial mechanism of reuterin, contributing to its potential application as a food preservative.Keywords:reuterin;3-hydroxypropionaldehyde;3-HPA;food biopreservative;Staphylococcus aureus;antibacterial mechanism;membrane damage;untargeted metabolomics
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DOI
PubMed
高影响因子
Foodborne Pathogens and Disease
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2024
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IF 1.9
Liu Qingyan,Shi Susu,Liu Shuanglin,Xian Youhua,Yan Haiyang,Yuan Yuan
Staphylococcus aureus contamination and prevention has always been a major concern for food industry. This work investigated the antibacterial activity and mechanisms of lauric acid (LA) against S. aureus. Results revealed 156 μg/mL was the minimum inhibitory concentration (MIC) for LA and it retarded growth rate of S. aureus. The inhibitory effect was enhanced with LA concentration. After being treated with 2 MIC LA for 24 h, the number of S. aureus decreased by 3.56 log colony-forming unit (CFU)/mL. Scanning electron microscopy profiling revealed that LA resulted in altered morphology of S. aureus cells. In addition, propidium iodide staining of flow cytometry suggested that LA treatment disrupted the cell membrane integrity. Changes in 8-anilino-1-naphthalenesulfonic acid fluorescence indicated a depolarization change in cell membrane fluidity. For practical applications, LA also displayed an antimicrobial potential in cooked chicken food model system, with 1.25–5 g/L of LA prolonging shelf life by 2 days at 4°C. Moreover, it had no adverse effect on pH values, color in cooked chicken meat, and even reduced lipid oxidation. To sum up, LA has great antimicrobial properties and is a candidate preservative for cooked meat food.
研究领域:
食品科学
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微生物学
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DOI
PubMed
高影响因子
PLoS One
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2024
·Vol. 19
·期 9
·e0310253
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IF 2.9
Zhaolei Wang,Haixia Du,Haofang Wan,Jiehong Yang,Haitong Wan
Methicillin-resistant Staphylococcus aureus (MRSA) is an opportunistic pathogen that can cause severe bacterial pneumonia. Amygdalin is the main active pharmaceutical ingredient of bitter almond, which has broad-spectrum antibacterial, anti-inflammatory, anti-oxidation and immunomodulatory effects. It is also the main ingredient of Yinhua Pinggan granule, which is commonly used to moisten the lung and relieve cough. However, little is known about the effects of amygdalin on MRSA. In this study, we found that amygdalin exhibited good antimicrobial activity in vitro against MRSA. Amygdalin has a protective effect on MRSA infected cells, and the effect is better when combined with levofloxacin. It also can reduce the adhesion and invasion of MRSA to cells. Amygdalin has anti-inflammatory and antioxidant effects, which can significantly reduce the increase of inflammatory factors and the production of ROS caused by infection. The protective mechanism of amygdalin on cells may be related to inhibiting the expression of NLRP3, ASC and IL-1β pyroptosis pathways. Taken together, our study suggests that amygdalin exerts antibacterial effects by affecting biofilm formation, the expression of virulence factors, and drug resistance genes. Amygdalin combined with levofloxacin has a protective effect on A549 cells infected with MRSA, and the mechanism may be related to the inhibition of inflammatory response, oxidative damage and pyroptosis.
研究领域:
药理学
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微生物学
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传染病学
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细胞生物学
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DOI
PubMed
高影响因子
ACS Applied Nano Materials
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2024
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IF 5.3
Xingxing Jiang,Aomei Zhang,Huan Gou,Xiang Chen,Lei Deng,Minghui Yang
Highly pathogenic bacterial infections are a major threat to human health, and the resulting drug resistance is beginning to pose a major clinical threat. To combat multidrug-resistant bacterial infections, there is an urgent need to develop antimicrobial drugs that are highly effective, environmentally friendly, and able to prevent the emergence of bacterial resistance. In this paper, Co4N nanozymes were successfully synthesized by pyrolysis of a presynthesized Co-containing metal organic framework (Co-MOF). Its peroxide and lactate oxidase activity and antimicrobial properties were investigated. Without the addition of exogenous H2O2, the nanozymes can initially generate H2O2 by catalyzing lactic acid and then produce highly active •OH from H2O2. This approach overcomes the obstacle of insufficient H2O2 to achieve a satisfactory antimicrobial effect. Furthermore, the local high temperature generated by Co4N under 808 nm laser irradiation further enhanced the antibacterial effect. These results showed that the nanozyme possesses broad-spectrum antimicrobial activity against Escherichia coli and Staphylococcus aureus, with an inhibition rate as high as 99% within 2 h. Meanwhile, the enzyme has good biocompatibility, paving a way for the application of MOF materials in biomedical fields.
研究领域:
生物医学
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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
高影响因子
FOOD CONTROL
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2025
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IF 6.3
Yixiang Sun,Liren Zhang,Huimin Wu,Hongjun Chen,Huijie Hu,Chongyu Zhang,Xiaoqiang Li,Yuan Li,Yimai Wang,Liqiang Luo,Yizhi Song
Methicillin-resistant Staphylococcus aureus (MRSA) has emerged as a significant pathogen of global concern, presenting substantial public health risks through foodborne transmission and contributing to elevated morbidity and mortality rates worldwide. The critical need for precise and timely identification of MRSA in food matrices has become increasingly paramount for effective public health protection. While numerous CRISPR-based detection platforms for MRSA have been recently developed, their widespread implementation has been hindered by intricate multi-step protocols and dependency on sophisticated instrumentation. In this study, we developed a direct, accurate and visual detection method for MRSA — the RPA-Cas12a-LFS method. This method comprises two main components: (1) the direct one-pot RPA-Cas12a system, which integrates bacterial lysis, RPA nucleic acid amplification, and CRISPR-Cas12a nucleic acid detection into a single step performed simultaneously at a constant temperature, and (2) the streptavidin-gold nanoparticles (SA-AuNP)-based CRISPR-specific lateral flow strip (LFS). By eliminating the need for nucleic acid extraction, this method significantly simplifies the experimental procedure and reduces the risk of cross-contamination. Through systematic optimization, this method demonstrated exceptional performance, enabling direct and specific identification of MRSA at remarkably low concentrations (10 CFU/mL) within 60 min in various milk samples. This advanced detection method, characterized by its direct sample processing, exceptional accuracy, visual interpretability, cost-efficiency, and minimal equipment requirements, is particularly suitable for on-site and real-time monitoring of pathogenic bacteria in the food industry.
研究领域:
微生物学
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食品安全
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分子诊断
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DOI
高影响因子
Nano Convergence
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2024
·Vol. 11
·期 1
·1-22
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IF 13.4
Chen Sunfang,Yao Jun,Huo Shicheng,Xu Chennan,Yang Ruting,Tao Danhua,Fang Bin,Ma Gaoxiang,Zhu Zaihua,Zhang Ye,Guo JingJing
Hydrogel-based delivery systems have now emerged as a pivotal platform for addressing chronic tissue defects, leveraging their innate capacity to suppress pathogenic infections and facilitate expedited tissue regeneration. In this work, an injectable hydrogel dressing, termed AgNPs-dermal matrix hydrogel (Ag@ADMH), has been designed to expedite the healing process of wounds afflicted with methicillin-resistant Staphylococcus aureus (MRSA), featuring sustained antibacterial efficacy. The synthesis of the hydrogel dressing entailed a self-assembly process of collagen fibers within an acellular dermal matrix to construct a three-dimensional scaffold, encapsulated with plant polyphenol-functionalized silver nanoparticles (AgNPs). The Ag@ADMH demonstrated exceptional biocompatibility, and enables a sustained release of AgNPs, ensuring prolonged antimicrobial activity. Moreover, the in vitro RT-qPCR analysis revealed that compared with ADMH, Ag@ADMH diminish the expression of iNOS while augmenting CD206 expression, thereby mitigating the inflammatory response and fostering wound healing. Especially, the Ag@ADMH facilitated a reduction in M1 macrophage polarization, as evidenced by a significant decrement in the M1 polarization trend and an enhanced M2/M1 ratio in dermal matrix hydrogels laden with AgNPs, corroborated by confocal microscopy and flow cytometry analyses of macrophage phenotypes. The in vivo assessments indicated that Ag@ADMH minimized fibrous capsule formation. In a full-thickness skin defect model of MRSA infection, the formulation significantly attenuated the inflammatory response by reducing MPO and CD68 expression levels, concurrently promoting collagen synthesis and CD34 expression, pivotal for vasculogenesis, thereby accelerating the resolution of MRSA-infected wounds. These attributes underscore the injectable extracellular matrix hydrogel as a formidable strategy for the remediation and regeneration of infected wounds. Graphical Abstract
研究领域:
生物材料学
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组织工程
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再生医学
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DOI
PubMed
高影响因子
MOLECULAR BIOLOGY REPORTS
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2025
·Vol. 53
·期 1
·82
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IF 2.8
Qi Xue,Hu Yanjun,Yang Jinghan,Jiang Mingxuan,Zhang Junhao,Du Yanting,Hu Changmin
Background The pathogenesis of bovine mastitis involves inflammation and cell death, with pyroptosis being a key factor in its development. Currently, antibiotics remain the primary therapeutic option for bovine mastitis, however, the increasing prevalence of antibiotic resistance constitutes a major public health threat. Selenium (Se) has been reported to alleviate inflammation primarily through its antioxidant properties, but the mechanism by which Se regulates pyroptosis in bovine mastitis remains unclear. Methods and results In this study, an in vitro mastitis model was established by infecting MAC-T cells with inactivated Staphylococcus aureus ( S. aureus ) (MOI = 10, 12 h). The results revealed that the mitochondrial membrane potential of the MAC-T cells in the infection group decreased significantly. Moreover, the accumulation of Reactive oxygen species (ROS) was accompanied by the activation of NOD-like receptor family containing pyrin domain 3 (NLRP3), the expression of the pyroptosis-related genes gasdermin D amino terminal fragment (GSDMD-N), and cysteine aspartate specific protease 1 (cleaved-caspase 1). Pretreatment with Se, the NLRP3 inhibitor MCC950 and the antioxidant N-acetylcysteine (NAC) attenuated mitochondrial damage, ROS accumulation, and the inhibition of pyroptosis. An in vivo mastitis model was established in mice fed a high-selenium diet (containing 1.5 mg/kg Se) and intramammarily injected with inactivated S. aureus (1 × 10 8 CFU/mL). Histological analysis revealed intact alveolar structure and reduced inflammatory cell infiltration in mice fed the high-selenium diet. The expression of the inflammasome NLRP3 downregulated, and the expression of GSDMD-N, a direct executor of pyroptosis, upregulated. Conclusion Our in vitro and in vivo results confirmed that Se alleviate mitochondrial damage and pyroptosis by inhibiting the NLRP3 pathway, ultimately alleviating mastitis. Graphical
研究领域:
兽医学
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免疫学
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分子生物学
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炎症与感染
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营养与代谢
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产品关联
DOI
PubMed
高影响因子
FOOD CONTROL
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2016
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IF 3.388
Can Xu,Jinglei Li,Liuqing Yang,Fang Shi,Liu Yang,Ming Ye
This study aimed to investigate the antibacterial activity of Lachnum YM30 intracellular melanin (LIM). The dilution method was used to measure the MIC and MBC of Gram-negative bacteria Escherichia coli, Salmonella typhi , Vibrio parahaemolyticus and Gram-positive bacteria Listeria monocytogenes , Bacillus megaterium , Staphylococcus aureus . MIC values for each bacterial strain were 0.4, 2.4, 0.2, 0.6, 0.8, 0.3 mg/mL, and the MBC values were 0.4, 3.2, 0.3, 0.8, 0.8, 0.4 mg/mL, respectively. Bacteriostasis of LIM against S. aureus (G + ) and V. parahaemolyticus (G − ) was further revealed by SEM observation, testing integrity of cell membrane, NPN uptake and membrane potential. MTT experiment was used to estimate the cell cytotoxicity of LIM. The results showed that LIM significantly damaged the integrity of cell membrane, increased the leakage of cell contents, raised the quantity of NPN uptake and reduced the membrane potential. LIM had no obvious cell cytotoxicity at low concentrations. These findings indicated that LIM had antibacterial activity and could be applied as a potential natural bacteriostatic agent in the food or pharmaceutical industry.
研究领域:
微生物学
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食品科学
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药理学
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DOI
高影响因子
Evidence-based Complementary and Alternative Medicine
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2022
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IF 2.65
Yixuan Sun,Fengjun Sun,Wei Feng,Qian Wang,Fang Liu,Peiyuan Xia,Xuewen Qiu
Owing to the fact that luteolin has antibacterial activity against Staphylococcus aureus (S. aureus) and methicillin-resistant S. aureus (MRSA), its specific mechanism in MRSA is worthy of investigation, which is the focus of this study. Initially, the collected S. aureus strains were treated with luteolin. Then, the minimum inhibitory concentration (MIC) of luteolin against the S. aureus strains was measured by the broth microdilution. The growth curves, biofilm formation, and cytotoxicity of treated S. aureus were detected using a microplate reader. The live and dead bacteria were evaluated using confocal laser scanning microscopy, the bacterial morphology was observed using scanning electron microscopy, and the S. aureus colony-forming unit (CFU) numbers were assessed. The levels of alpha hemolysin (α-hemolysin), delta hemolysin (δ-hemolysin), and hlaA were detected via western blot and RT-PCR. The mortality of mouse model with S. aureus systemic infection was analyzed, and the levels of IL-6, IL-8, IL-10, and TNF-α were quantitated using ELISA. Concretely, the MIC of luteolin against MRSA N315 was 64 μg/mL. Luteolin at 16 μg/mL did not affect the growth of MRSA N315, but inhibited the biofilm formation and CFU, and promoted the morphological changes and death of MRSA N315. Luteolin decreased the cytotoxicity and the levels of α-hemolysin, δ-hemolysin, and hlaA in MRSA N315, elevated MRSA-reduced mice survival rate, and differentially modulated the inflammatory cytokine levels in MRSA-infected mice. Collectively, luteolin inhibits biofilm formation and cytotoxicity of MRSA via blocking the bacterial toxin synthesis.
研究领域:
微生物学
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药理学
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免疫学
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传染病学
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DOI
PubMed
高影响因子
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