Genes
·
2019
·Vol. 10
·期 6
·412
·
IF 3.331
Zhangxun Wang,Hong Zhu,Yuran Cheng,Yuanyuan Jiang,Yuandong Li,Bo Huang
The polyubiquitin gene is a highly conserved open reading frame that encodes different numbers of tandem ubiquitin repeats from different species, which play important roles in different biological processes.Metarhizium robertsiiis a fungal entomopathogen that is widely applied in the biological control of pest insects. However, it is unclear whether the polyubiquitin gene is required for fungal development, stress tolerance, and virulence in the entomopathogenic fungus. In the present study, the polyubiquitin gene (MrUBI4, MAA_02160) was functionally characterized via gene deletion inM. robertsii.Compared to the control strains, theMrUBI4deletion mutant showed delayed conidial germination and significantly decreased conidial yields (39% of the wild-type 14 days post-incubation). Correspondingly, the transcript levels of several genes from the central regulatory pathways associated with conidiation, includingbrlA,abaA,andwetA, were significantly downregulated, which indicated thatMrUBI4played an important role in asexual sporulation. Deletion ofMrUBI4especially resulted in increased sensitivity to ultraviolet (UV) and heat-shock stress based on conidial germination analysis between mutant and control strains. The significant increase in sensitivity to heat-shock was accompanied with reduced transcript levels of genes related to heat-shock protein (hsp), trehalose, and mannitol accumulation (tps,tpp,nth,andmpd) in theMrUBI4deletion mutant. Deletion ofMrUBI4has no effect on fungal virulence. Altogether,MrUBI4is involved in the regulation of conidiation, conidial germination, UV stress, and heat-shock response inM. robertsii.Keywords:Metarhizium robertsii;polyubiquitin;conidiation;conidial germination;stress tolerance
研究领域:
真菌学
·
分子生物学
·
植物保护
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Analytical Methods
·
2023
·
IF 3.1
Mengya Li,Shijie Liu,Shiliang Guo,Dong Liang,Miaoyun Li,Yaodi Zhu,Lijun Zhao,Jong-Hoon Lee,Gaiming Zhao,Yangyang Ma,Yanxia Liu
A study on the inactivation and germination mechanism of spores is very important in the application of spores, as such high-purity spores are the basis of related research. However, spores and vegetative cells of bacteria often coexist, and it is difficult to separate them. In this study, a magnetic flow device for the purification of spores in the culture medium system was developed based on a “stepped” structure with a magnetic force that could absorb vegetative cells with magnetic nanoparticles. The operation process was as follows: first, vancomycin functionalized nanoparticles were used to prepare Van-Fe3O4 NPs, which were then combined with vegetative cells to form a magnetic conjugate. Subsequently, the magnetic conjugate (vegetative cells) flowed through the “stepped” magnetic flow device and was adsorbed. Meanwhile, the spores moved through the channel and were collected. The achieved purity of the collected spores was more than 95%. Further, the number of the obtained spores was quickly quantified using Raman spectroscopy. The entire purification and quantitative process can be completed within 30 min and the limit of detection was 5 CFU mL−1. This study showed outstanding spore purification ability and provided a new method for purification and rapid quantitative detection of spores.
研究领域:
微生物学
·
分析化学
·
生物技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Frontiers in Microbiology
·
2021
·
IF 5.64
Fan Qiuxia,Liu Cheng,Gao Zhenpeng,Hu Zhongqiu,Wang Zhouli,Xiao Jianbo,Yuan Yahong,Yue Tianli
Alicyclobacillus acidoterrestris (A. acidoterrestris), a spore-forming bacterium, has become a main challenge and concern for the juices and acid beverage industry across the world due to its thermo-acidophilic characteristic. Thymoquinone (TQ) is one of the active components derived from Nigella sativa seeds. The objective of this study was to investigate antibacterial activity and associated molecular mechanism of TQ against A. acidoterrestris vegetative cells, and to evaluate effects of TQ on A. acidoterrestris spores and biofilms formed on polystyrene and stainless steel surfaces. Minimum inhibitory concentrations of TQ against five tested A. acidoterrestris strains ranged from 32 to 64 μg/mL. TQ could destroy bacterial cell morphology and membrane integrity in a concentration-dependent manner. Field-emission scanning electron microscopy observation showed that TQ caused abnormal morphology of spores and thus exerted a killing effect on spores. Moreover, TQ was effective in inactivating and removing A. acidoterrestris mature biofilms. These findings indicated that TQ is promising as a new alternative to control A. acidoterrestris and thereby reduce associated contamination and deterioration in the juice and acid beverage industry.
研究领域:
食品科学
·
微生物学
✓ 已验证
DOI
PubMed
高影响因子
LWT-FOOD SCIENCE AND TECHNOLOGY
·
2023
·
IF 6
Yan Zhu,Yuanyuan Yao,Jinfeng Xi,Caiguo Tang,Lifang Wu
Fusarium graminearum ( F. graminearum ) is a vital pathogen of Fusarium head blight (FHB). Hydrogen sulfide (H 2 S), which can be induced by stress in plants as a fungal inhibitor, affects the germination of spores through the detection of environmental factors such as temperature and pH. Based on mathematical models, F. graminearum was treated with different temperatures, pH, and H 2 S concentration to investigate spore germination events. This paper considered the synergistic effects of temperature and pH on spores in order to determine the optimal germination environment. Under these circumstances, the inhibition of spore germination with different concentrations of H 2 S was quantified. The results suggested that the germination time negatively correlates with the germinating rate. An increase in temperature altered the weak alkali preference of F. graminearum spores. At 28 °C, spores were more sensitive to the changes in pH. H 2 S gas could delay the germinating process significantly, however the required H 2 S concentration varied with environmental changes. This paper provides a perspective on the synergistic effect of temperature and pH on spore germination and contributes to determining the concentration of H 2 S as a management of FHB.
研究领域:
植物病理学
·
微生物学
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF FOOD ENGINEERING
·
2024
·
IF 5.3
Xiaodan Guo,Lei Zhang,Xinian Li,Xiaojing Ren,Jian Yu,Tianli Yue,Fangyu Long
High hydrostatic pressure (HHP) is widely used to inactivate microorganisms in food, but achieving effective spore inactivation by conventional HHP remains challenging due to their resistance. The present study compared the effectiveness of continuous, intermittent and induced inactivation HHP techniques for inactivation of Alicyclobacillus acidoterrestris spores. Under optimal induced inactivation conditions (200 MPa/4 cycles, 600 MPa/2 cycles), reductions of 0.79 log CFU/mL for the highly resistant DSM3922 spores and 1.94 log CFU/mL for the less resistant DSM3924 spores were achieved. Mechanistic investigations revealed that: (Ⅰ) structural damage, including breakage, wrinkling, and concavity, was induced in spores post-HHP treatment; (Ⅱ) pulsation forces generated by repeated pressurization and depressurization during induced inactivation HHP reduced the D90 values of the spore aggregates to 99.37 μm for DSM3922 and 76.49 μm for DSM3924, enhancing the inactivation efficacy; (Ⅲ) the inner membrane (IM) and cortex were severely impaired, while nucleic acid and protein leakage from spores significantly increased after HHPs. To further enhance spore inactivation, Tea Tree, Nutmeg, Eucalyptus, and Litsea cubeba essential oils (EOs) were selected from twelve EOs as safe and effective antimicrobial substances that synergize with HHP. Combining 5% Litsea cubeba EO with HHP (200 MPa/4 cycles, 600 MPa/2 cycles) resulted in reductions of 2.57 log CFU/mL for DSM3922 and 5.08 log CFU/mL for DSM3924. These findings suggest that the combination of HHP and EOs could be a promising approach for inactivating A. acidoterrestris spores.
研究领域:
食品科学
·
微生物学
✓ 已验证
产品关联
DOI
高影响因子
LWT-FOOD SCIENCE AND TECHNOLOGY
·
2019
·
IF 3.714
Rui Cai,Mingquan Zhang,Lu Cui,Yahong Yuan,Yifei Yang,Zhouli Wang,Tianli Yue
Alicyclobacillus acidoterrestris has received much attention due to its unique thermo-acidophilic property and implication in the spoilage of pasteurized juices. The aim of this study was to investigate the antibacterial characteristics and mechanisms of thymol against A. acidoterrestris vegetative cells and spores. Minimum inhibition concentration (MIC) and minimum bactericidal concentration (MBC) of thymol against vegetative cells were both 0.25 mg/mL. MIC of thymol against spores was 0.5 mg/mL, and the MBC was greater than 1.0 mg/mL. Thymol could effectively inhibit A. acidoterrestris growth, spore germination and guaiacol production. When treated by thymol, the leakage of nucleic acids and proteins from A. acidoterrestris cells and spores increased significantly. SDS-PAGE investigation of bacterial proteins showed that the loss of soluble proteins was obvious as well. Scanning electron microscopy observation exhibited that A. acidoterrestris cells or spores treated with thymol had a severe morphological damage. These results demonstrated that thymol exerted its good antibacterial activities by destroying the integrity of the cell and spore. This study provides a new method for the inactivation of A. acidoterrestris in fruit juice.
研究领域:
食品科学
·
微生物学
✓ 已验证
DOI
高影响因子
BRAZILIAN JOURNAL OF MICROBIOLOGY
·
2022
·Vol. 53
·期 2
·547-556
·
IF 2.214
Sun Xiaodong,Kong Xiangxiang,Li Chunxia,Wang Minjia,Yi Jialin,Deng Zhirui,Niu Bing,Chen Qin
Previous studies have shown that the combination disinfectant, Ortho -phthalaldehyde and benzyldimethyldodecylammonium chloride (ODB), can effectively kill a variety of microorganisms, such as Escherichia coli , Staphylococcus aureus , and Candida albicans . To observe the sporicidal ability and mechanism of ODB for spores, Bacillus subtilis spores were used as the research object in this experiment. TEM images revealed that ODB destroyed the integrity of the coat, cortex, and inner membrane of the spores after 0.5-h treatment, and the nuclear material was also broken and exuded after 4-h treatment. The broken structure led to the release of dipicolinic acid (DPA) in large amount. The results show that B. subtilis spores can be effetely killed by ODB through destroying the structure of the spores.
研究领域:
微生物学
·
消毒科学
·
生物技术
✓ 已验证
DOI
PubMed
高影响因子
INTERNATIONAL DAIRY JOURNAL
·
2024
·
IF 3.1
Yiwei Xu
The presence of Heyndrickxia sporothermodurans is a widespread concern in dairy industry due to its highly thermal-resistant spores. The "Cleaning-in-place" (CIP) system is the primary method used by dairy industry to control them. But the food safety-related properties of H. sporothermodurans remain poorly understood. Thus, this study proposes to determine the growth characteristics and sporulation of H. sporothermodurans in different matrices, as well as the efficacy of various disinfectants against its biofilm and spore. Therefore, the growth of vegetative cell and spore germination in rich media (brain heart infusion, BHI) and ultra-high temperature (UHT) milk for at least 360 h was investigated in this research. In addition, the biofilms of different maturity induced on stainless steel surfaces were sanitized simulating a CIP procedure, using disinfectants (200 mg/mL peracetic acid, 1.5% sodium hydroxide and 1% nitric acid). Scanning electronic microscopy (SEM) was used as a complementary technique to observe the conditioning of the stainless steel surface after 10 d. Subsequently, the effects of these sanitation methods against the spore were performed in 96-well plates. The observation of growth behavior revealed that the vegetative cells and spore cells may be interconverted in a nutrient-rich environment, resulting in a balanced mode in which spores account for approximately 0.1% of the total cells. This could be used to anticipate the number of contaminated bacteria in a UHT plant environment. The sterilization efficiency tests showed that these sanitation methods were efficient against biofilms but not against spores. Therefore, new inactivation strategies against spores should be proposed and should focus on spores adhesion and the biofilms induced by spores.
研究领域:
微生物学
·
食品安全
·
乳品科学
✓ 已验证
DOI
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
·
2025
·
IF 7.7
Xinxin Wang,Shan Sun,Ke Cheng,Tao Lin,Henggang Wang,Haoyi Sun,Hengwei Lin,Peng Wang
Pathogenic bacterial spores pose a considerable threat to human health due to their ability to survive extreme environmental conditions. Thus, sensitive detection and efficient inactivation of these spores are essential for preventing disease transmission. However, most existing studies have predominantly concentrated on detection alone. Herein, we developed a versatile nanoplatform that integrates sensitive bacterial spore sensing and in situ spore inactivation capabilities by assembling terbium ions (Tb 3+ ) with photosensitizing carbon dots (CDs), referred to as Tb-CDs nanoassemblies (NAs). By leveraging the unique optical properties of CDs and Tb 3+ ions, along with the antenna effect of lanthanides, Tb-CDs NAs demonstrated highly sensitive visual detection of the key bacterial spore biomarker, pyridinedicarboxylic acid (DPA), achieving a low detection limit of 0.68 μM and excellent selectivity. Additionally, Tb-CDs NAs exhibited practical sensing capabilities in various environments, including spore suspensions and real samples, while monitoring bacterial spore germination. Further studies confirmed that the DPA-triggered disassembly of Tb-CDs NAs led to the release of CDs, enabling higher affinity for spores and in situ inactivation through singlet oxygen generation. This work underscores the potential of CDs-based assemblies for simultaneous pathogen detection and inactivation, providing promising tools for preventing bacterial spread and contamination.
研究领域:
生物传感
·
微生物学
·
纳米医学
✓ 已验证
产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2024
·
IF 8.1
Zhuoya Hao,Jiacheng Zhang,Qin Peng,Xuefeng Tian,Jun Zhang,Jiayi Ai,Qiqi Jia,Yihui Yuan,Ning Wang
The increasing global reliance on nuclear energy highlights the critical need for uranium recovery from nuclear wastewater. However, due to the harsh environment of concentrated acid and nuclear radiation, the development of new adsorbent for uranium recovery from nuclear wastewater is highly needed. The bacterial spore has been reported to exhibit high tolerance to these harsh environments and contain functional components with reliable uranium binding ability, while there is still no report on the use of bacterial spore for uranium recovery from nuclear wastewater. Herein, the potential of the bacterial spore for being used in uranium recovery was analyzed for the first time. The result shows that the bacterial spore realizes a high uranium adsorption capacity of 245 mg g −1 in uranium-containing aqueous environment. With a low dosage of 0.1 g L −1 , the bacterial spore achieves a high uranium removal performance of 99.03 % in simulated nuclear wastewater. Additionally, when the concentration of HNO 3 reached 12 M, the adsorption capacity can still reach 156 mg g −1 after 24 h of treatment, proving its high tolerance to concentrated acid. Moreover, after being irradiated by γ-ray with the radiation dosage of 500 kGy, the bacterial spore retains 95.94 % of the uranium adsorption capacity, indicating its high resistance to nuclear radiation. These findings indicate that the bacterial spore would be a highly potential adsorbent for the recovery of uranium from nuclear wastewater with concentrated acid and nuclear radiation.
研究领域:
环境科学
·
微生物学
✓ 已验证
产品关联
DOI
高影响因子
FOOD MICROBIOLOGY
·
2024
·
IF 4.5
Qiaoyun Wei,Yuan Yuan,Jianhao Zhang,Jin Wang
This study investigated the fungicidal efficiency and mechanism of action of dielectric barrier discharge cold atmosphere plasma (DBD-CAP) in inactivating Aspergillus niger ( A. niger ) spores. The disinfection efficacy and quality of dried jujube used as the processing application object were also studied. The results indicated that the Weibull + Tail model performed better for spore inactivation curves at different voltages among various treatment times, and the spore cells were reduced by 4.05 log (cfu/mL) in spores suspension at 70 kV after 15 min of treatment. This disinfection impact was further supported by scanning electron microscope (SEM) and transmission electron microscopy (TEM) images, which showed that the integrity of the cell membrane was damaged, and the intracellular content leaked out after DBD-CAP treatment. Elevated levels of reactive oxygen species (ROS) during the treatment increased the relative conductivity of cells, and leakage of nucleic acids and proteins further supported the disinfection impact. Additionally, the growth and toxicity of surviving A. niger spores after treatment were also greatly reduced. When DBD-CAP was applied to disinfecting dried jujube, the spore number exhibited a 2.67 log cfu/g reduction after treatment without significant damage observed onto the quality ( P > 0.05 ).
研究领域:
食品科学
·
微生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Algal Research-Biomass Biofuels and Bioproducts
·
2025
·
IF 4.5
Haihong Chen,Ziyan Shi,Zhihai Zhong,Nanjing Ji,Xiaoqian Zhou,Zhijie Dan,Xin Shen
Oxidative stress from mechanical injury can trigger the development of Wound-Induced Spores (WIS) in Pyropia yezoensis , yet the regulatory mechanisms underlying this process require further elucidation. In this study, comparative transcriptomic analysis between injured and uninjured P. yezoensis thalli revealed significant differential gene expression within the glutathione (GSH) metabolism pathway during WIS development. There was a down-regulation in the expression of genes encoding for γ-glutamyl-cystein synthetase (GCL) and glutathione synthetase (GSS), which were pivotal for GSH biosynthesis, during the development of WIS. Moreover, a diminished expression level was also observed in genes associated with oxidative metabolism of GSH during this process, including those encoding glutathione S-transferase (GST), glutathione peroxidase (GPX), glutathione reductase (GR), ascorbate peroxidase (APX), monodehydroascorbate reductase (MDHAR), and dihydroascorbate reductase (DHAR). However, this transcriptional regulation does not correspond to a significant decrease in intracellular GSH levels, which may be associated with a reduction in the oxidative metabolism of GSH, leading to decreased cellular utilization of GSH. Treatment injured P. yezoensis with Buthionine sulfoximine (BSO) promoted the release probability of WIS, the release efficiency of WIS and germination rate of asexual spores, while supplementation of GSH produced opposite results, suggesting that modulating GSH levels can regulate the release of WIS. Correlation analysis suggested that there was a significant positive correlation between the release of WIS and the germination rate of asexual spores, suggesting that promoting the release of WIS could lead to the acquisition of a greater number of asexual spore seedlings. Our findings underscore the key role of GSH metabolism in WIS regulation and provide a theoretical foundation for the subsequent development of strategies to obtain asexual spore seedlings.
研究领域:
植物学
·
分子生物学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）