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利用微量热法研究Cd^(2+)和Cu^(2+)对嗜热四膜虫(Tetrahymena thermophila)的毒性效应 被引量:12
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作者 陈小娟 沈韫芬 +2 位作者 刘义 冯伟松 缪炜 《应用与环境生物学报》 CAS CSCD 2004年第6期745-749,共5页
利用微量热法研究Cd2 + 和Cu2 + 对嗜热四膜虫BF5(TetrahymenathermophilaBF5)生长代谢毒性效应 ,结果表明 :①低浓度的Cd2 + (0~ 0 .4mgL-1)和Cu2 + (0~ 10mgL-1)对四膜虫的生长有促进作用 ,而高浓度的Cd2 + (0 .8~ 3.2mgL-1)和Cu2 ... 利用微量热法研究Cd2 + 和Cu2 + 对嗜热四膜虫BF5(TetrahymenathermophilaBF5)生长代谢毒性效应 ,结果表明 :①低浓度的Cd2 + (0~ 0 .4mgL-1)和Cu2 + (0~ 10mgL-1)对四膜虫的生长有促进作用 ,而高浓度的Cd2 + (0 .8~ 3.2mgL-1)和Cu2 + (2 0~ 2 0 0mgL-1)则产生抑制作用 ;②Cd2 + 和Cu2 + 的半抑制浓度IC50 分别为 2 .0 4mg/L和15 5 .5mg/L ;③联合毒性为协同作用 ;④微量热法所得Cd2 + 和Cu2 + 单独作用时的IC10 分别为 0 .96mg/L和 19.9mg/L ,高于种类损伤法结果 ;⑤微量热法所得Cd2 + 和Cu2 + 单独作用时的IC10 均高于II级饮用水水质标准 .而Cd2 + 和Cu2 +间的协同作用使Cd2 + 的IC10 降低为 0 .31mg/L ,高于水质标准 ;Cu2 + 的IC10 降低为 1.16mg/L ,与水质标准相近 .总之 ,微量热法不仅是一种快速评价污染物毒性效应的新方法 ,而且可用于相关的环境毒理学理论研究 .图 1表 5参 展开更多
关键词 微量热 CD^2+ CU^2+ 嗜热四膜虫 联合毒性 种类损伤法
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关键环境因子对嗜肺军团菌(Legionella pneumophila)在嗜热四膜虫(Tetrahymena thermophila)细胞内增殖的影响 被引量:2
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作者 黄绍松 徐润林 +3 位作者 马林 冯文如 何晖 陆勇军 《应用与环境生物学报》 CAS CSCD 北大核心 2007年第4期510-514,共5页
嗜肺军团菌是一种生活在人工水环境中的条件性致病菌,环境条件对该菌的存活和胞内增殖具有重要的影响.本文用作者建立的军团菌-四膜虫模型,研究了空调水池水、Fe3+和感染温度3种关键性环境因子对嗜肺军团菌在嗜热四膜虫宿主细胞内增殖... 嗜肺军团菌是一种生活在人工水环境中的条件性致病菌,环境条件对该菌的存活和胞内增殖具有重要的影响.本文用作者建立的军团菌-四膜虫模型,研究了空调水池水、Fe3+和感染温度3种关键性环境因子对嗜肺军团菌在嗜热四膜虫宿主细胞内增殖的影响.结果发现,尽管空调水中Fe3+浓度大大低于培养基中的Fe3+浓度,但适合嗜肺军团菌在嗜热四膜虫宿主胞内的存活和增殖;感染缓冲液中的Fe3+能够被嗜热四膜虫富集,并被胞内的军团菌加以利用,缓冲液中浓度0.05×10-6的Fe3+即可显著促进胞内军团菌的增殖,但0.1×10-6和0.5×10-6的Fe3+促进军团菌胞内增殖的效果差异不显著;较高的温度对军团菌的胞内增殖也有明显促进作用,35℃时,即使感染复数等于10,军团菌也可进行胞内复制扩增,并最终裂解宿主细胞. 展开更多
关键词 嗜肺军团菌 嗜热四膜虫 环境因子 胞内增殖
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Metabolomic Fingerprint of the Model Ciliate, Tetrahymena thermophila Determined by Untargeted Profiling Using Gas Chromatography-Mass Spectrometry 被引量:1
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作者 XU Jing BO Tao +1 位作者 SONG Weibo WANG Wei 《Journal of Ocean University of China》 SCIE CAS CSCD 2019年第3期654-662,共9页
The ciliate Tetrahymena is a valuable model organism in the studies of ecotoxicology. Changes in intracellular metabolism are caused by exogenous chemicals in the environment. Intracellular metabolite changes signify ... The ciliate Tetrahymena is a valuable model organism in the studies of ecotoxicology. Changes in intracellular metabolism are caused by exogenous chemicals in the environment. Intracellular metabolite changes signify toxic effects and can be monitored by metabolomics analysis. In this work, a protocol for the GC-MS-based metabolomic analysis of Tetrahymena was established. Different extraction solvents showed divergent effects on the metabolomic analysis of Tetrahymena thermophila. The peak intensity of metabolites detected in the samples of extraction solvent Formula 1(F1) was the strongest and stable, while 61 metabolites were identified. Formula 1 showed an excellent extraction performance for carbohydrates. In the samples of extraction solvent Formula 2(F2), 66 metabolites were characterized, and fatty acid metabolites were extracted. Meanwhile, 57 and 58 metabolites were characterized in the extraction with Formula 3(F3) and Formula 4(F4), respectively. However, the peak intensity of the metabolites was low, and the metabolites were unstable. These results indicated that different extraction solvents substantially affected the detected coverage and peak intensity of intracellular metabolites. A total of 74 metabolites(19 amino acids, 11 organic acids, 2 inorganic acids, 11 fatty acids, 11 carbohydrates, 3 glycosides, 4 alcohols, 6 amines, and 7 other compounds) were identified in all experimental groups. Among these metabolites, amino acids, glycerol, myoinositol, and unsaturated fatty acids may become potential biomarkers of metabolite set enrichment analysis for detecting the ability of T. thermophila against environmental stresses. 展开更多
关键词 TETRAHYMENA thermophila metabolomics ECOTOXICOLOGY gas chromatography-mass SPECTROMETRY
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Myceliophthora thermophila漆酶与木质素模型物的对接研究
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作者 刘浩 孙见良 +2 位作者 Puneet K.SINGH 杨文萍 付时雨 《华南理工大学学报(自然科学版)》 EI CAS CSCD 北大核心 2017年第11期112-119,共8页
漆酶催化木质素氧化聚合或降解是自然界碳循环的重要环节,其作用机制一直是生物质科学领域的研究热点.文中采用分子模拟技术进行研究,首先构建Myceliophthora thermophila(Mth)漆酶的3D模型,然后用9种木质素模型物在Mth漆酶T_1Cu口袋区... 漆酶催化木质素氧化聚合或降解是自然界碳循环的重要环节,其作用机制一直是生物质科学领域的研究热点.文中采用分子模拟技术进行研究,首先构建Myceliophthora thermophila(Mth)漆酶的3D模型,然后用9种木质素模型物在Mth漆酶T_1Cu口袋区做分子对接.结果表明,Mth漆酶中4个Cu离子与高度保守的4个氨基酸片段结合,Mth漆酶与Melanocarpus albomyces漆酶亲缘关系最近(Identity值>74%),以之为模板可得到高质量的3D模型,Ramachandran Plot分析证明模型中所有氨基酸构象都是合理的.在Mth漆酶T_1Cu活性口袋区,木质素单体与Ala192、Lys188和Trp507氢键结合,脂肪链端羧基化会影响Trp507形成氢键,若酚羟基邻位被双甲氧基取代,则会降低单体的结合能.木质素模型物聚合度越高,结合能越低,二者线性相关.由于空间位阻效应,四聚体不能进入活性口袋,需要介体才能被Mth漆酶催化氧化. 展开更多
关键词 分子对接 Myceliophthora thermophila漆酶 木质素模型物 活性口袋 官能团 结合能
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Effects of pyraclostrobin on growth,oxidative stress,and gene expression in relation to stress and ATP-binding cassette transporters in Tetrahymena thermophila
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作者 Yang LIU Jiale ZHANG +4 位作者 Peng XIAO Xin LIU Yisifu MA Jing ZHANG Bangjun ZHANG 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2024年第1期150-162,共13页
Pyraclostrobin(PYR),a widely used fungicide,has negative effects on fish and algae,but its toxicity in protozoa remains unclear.In this study,the effects of PYR on the growth,oxidative stress,and gene expression relat... Pyraclostrobin(PYR),a widely used fungicide,has negative effects on fish and algae,but its toxicity in protozoa remains unclear.In this study,the effects of PYR on the growth,oxidative stress,and gene expression related to stress and ATP-binding cassette(ABC)transporters in Tetrahymena thermophila were investigated.The result showed that the 96-h IC_(50)of PYR against T.thermophila was 17.2 mg/L.Moreover,PYR inhibited the growth of T.thermophila in concentration-or time-dependent manner.A morphological study revealed that the shape and size of T.thermophila changed,and damage of cell membrane surface was observed by scanning electron microscopy after 96 h of PYR exposure.The activities of superoxide dismutase(SOD)and catalase(CAT)increased throughout the experiment.In contrast,the glutathione(GSH)content was increased at 24 h and 48 h of exposure and decreased at 96 h.Moreover,a significant increase in malondialdehyde(MDA)level was observed in T.thermophila after96 h of exposure.Furthermore,PYR upregulated the HSP703,HSP705,GPx2,and ABAC15 gene expression in the 0.1–5-mg/L groups and downregulated the HSP704,HSP90,TGR,and ABCC52 mRNA levels at 96 h of exposure.These results suggest that PYR may exert adverse effects on T.thermophila by inducing oxidative stress and changing the gene expression related to ABC transporters and stress,which may enrich the understanding of the toxicity mechanism of PYR in aquatic organisms and provide reference data for aquatic ecological risk assessments. 展开更多
关键词 PYRACLOSTROBIN Tetrahymena thermophila GROWTH oxidative stress gene expression
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诱导嗜热四膜虫(Tetrahymena thermophila)细胞凋亡样变化的研究 被引量:2
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作者 艾斯卡尔.依米提 庞延斌 《细胞生物学杂志》 CSCD 2000年第3期140-145,共6页
本文以单细胞真核生物嗜热四膜虫(Te-trahymena thermophila)作为实验材料以抗肿瘤药物高三尖杉脂碱(Homoharringtonine,HHT)、糖皮质激素类药物地塞米松(9α-Fluo-ro-16α-methylprednisolone,Dex)和抗生素类药物放线菌素D(Actinomycin... 本文以单细胞真核生物嗜热四膜虫(Te-trahymena thermophila)作为实验材料以抗肿瘤药物高三尖杉脂碱(Homoharringtonine,HHT)、糖皮质激素类药物地塞米松(9α-Fluo-ro-16α-methylprednisolone,Dex)和抗生素类药物放线菌素D(Actinomycin D)诱导嗜热四膜虫凋亡并研究其细胞凋亡过程的生物化学特性。结果表明抗肿瘤药物及抗生素类药物均不能明显地诱导嗜热四膜虫细胞凋亡。但糖皮质激素类药物在含一定量的Ca^(2+)、Mg^(2+)离子时能诱导嗜热四膜虫发生凋亡。作者认为诱导嗜热四膜虫凋亡过程可能与糖皮质激素类药物诱导鼠胸腺细胞凋亡的机制是类似的,嗜热四膜虫与胸腺细胞的凋亡过程可能同样被Ca^(2+)、Mg^(2+)离子依赖性的核酸内切酶的活化机制所控制着。 展开更多
关键词 嗜热四膜虫 细胞调亡 细胞形态
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水热预处理与Myceliophthora thermophila复合酶协同高效降解混合生物质的研究
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作者 钱玉霞 邱卫华 任虹 《化学与生物工程》 CAS 2020年第11期34-41,共8页
以甘蔗渣-棉杆-小麦秸秆(4∶2∶1,质量比)混合生物质为研究对象,考察了水热预处理参数对混合生物质中各组分含量的影响,研究了嗜热毁丝霉(Myceliophthora thermophila)复合酶(MTE)与纤维素酶(Cel)协同作用下水热预处理混合生物质的酶解... 以甘蔗渣-棉杆-小麦秸秆(4∶2∶1,质量比)混合生物质为研究对象,考察了水热预处理参数对混合生物质中各组分含量的影响,研究了嗜热毁丝霉(Myceliophthora thermophila)复合酶(MTE)与纤维素酶(Cel)协同作用下水热预处理混合生物质的酶解效率,并对酶解液及酶解渣分别进行UV、FTIR分析。结果表明,水热预处理温度是影响混合生物质中各组分含量变化的主要因素,在相近水热预处理强度下,经150℃维温30 min和180℃维温5 min处理的混合生物质中木质素含量分别为(26.50±1.33)%和(29.40±1.35)%。MTE对Cel具有明显的协同作用,且受水热预处理温度的影响较大。MTE对经160℃维温10 min处理的混合生物质的Cel酶解协同效率最高达(53.60±2.68)%,酶解总糖得率达(75.50±3.77)%;而继续升高温度或者延长维温时间,虽然酶解总糖得率略有升高,但MTE的协同酶解效率快速降低。UV和FTIR分析表明,MTE所含的木质纤维素分解酶和木质素氧化酶可在较低预处理强度下协同Cel提高混合生物质的酶解效率。 展开更多
关键词 混合生物质 水热预处理 嗜热毁丝霉 协同酶解
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MTD:A cloud-based omics database and interactive platform for Myceliophthora thermophila
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作者 Jiacheng Dong Zhitao Mao +10 位作者 Haoran Li Ruoyu Wang Yutao Wang Haokai Jia Jingen Li Qian Liu Chenglin Zhang Xiaoping Liao Defei Liu Hongwu Ma Chaoguang Tian 《Synthetic and Systems Biotechnology》 2025年第3期783-793,共11页
Nowadays,biological databases are playing an increasingly critical role in biological research.Myceliophthora thermophila is an excellent thermophilic fungal chassis for industrial enzyme production and plant biomass-... Nowadays,biological databases are playing an increasingly critical role in biological research.Myceliophthora thermophila is an excellent thermophilic fungal chassis for industrial enzyme production and plant biomass-based chemical synthesis.The lack of a dedicated public database has made access to and reanalysis of M.thermophila data difficult.To bridge this gap,we developed MTD(https://mtd.biodesign.ac.cn/),a cloud-based omics database and interactive platform for M.thermophila.MTD integrates comprehensive genome annotations,sequence-based predictions,transcriptome data,curated experimental descriptions,and bioinformatics analysis tools,offering a comprehensive,one-stop solution with a‘top-down’search strategy to streamline M.thermophila research.The platform supports data reproduction,rapid querying,and in-depth mining of existing tran-scriptome datasets.Based on analyses using data and tools in MTD,we identified shifts in metabolic allocation in a glucoamylase hyperproduction strain of M.thermophila,highlighting changes in fatty acid biosynthesis and amino acids biosynthesis pathways,which provide new insights into the underlying phenotypic alterations.As a pioneering resource,MTD marks a key advancement in M.thermophila research and sets the model for developing similar databases for other species. 展开更多
关键词 Myceliophthora thermophila DATABASE Omics data Serverless architecture
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嗜热拟青霉耐热阿拉伯木聚糖酶的异源表达及其对麦芽糖化的影响
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作者 杨行 张文姣 +4 位作者 闫协民 赵伟 江正强 闫巧娟 杨绍青 《食品工业科技》 北大核心 2026年第1期189-196,共8页
目的:发掘耐热木聚糖酶并探究其在麦芽糖化中的应用潜力。方法:克隆嗜热拟青霉(Paecilomyces thermophila)J18木聚糖酶(PtXynA)基因,将其在黑曲霉中进行异源表达,在5 L发酵罐中采用液体深层发酵制备重组酶(PtXynA),进一步探究酶的酶学性... 目的:发掘耐热木聚糖酶并探究其在麦芽糖化中的应用潜力。方法:克隆嗜热拟青霉(Paecilomyces thermophila)J18木聚糖酶(PtXynA)基因,将其在黑曲霉中进行异源表达,在5 L发酵罐中采用液体深层发酵制备重组酶(PtXynA),进一步探究酶的酶学性质,最后评价重组酶在麦芽糖化中的应用效果。结果:重组菌经液体深层发酵96 h后,木聚糖酶的酶活力达到904.0 U/mL,蛋白含量为1.4 mg/mL。重组酶在pH7.0和70℃下表现出最高酶活力,在pH5.5~9.0和75℃以下保持稳定。PtXynA显示出严格的底物特异性,对小麦阿拉伯木聚糖(1993.2 U/mg)的比酶活力最高,其次为燕麦木聚糖(1782.5 U/mg)、榉木木聚糖(1552.0 U/mg)和桦木木聚糖(1238.7 U/mg)。在麦芽糖化过程中添加木聚糖酶(200 U/g麦芽),麦芽汁的过滤时间和黏度分别降低了43.9%和10.8%。结论:PyXynA具有优良的酶学特性,在啤酒糖化过程中显示出较大应用潜力。 展开更多
关键词 嗜热拟青霉 异源表达 嗜热木聚糖酶 阿拉伯木聚糖酶 麦芽糖化
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Toxicity of Five Herbs in Aconitum L. on Tetrahymena thermophila Based on Spectrum-effect Relationship 被引量:6
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作者 Xiao-jiao Sun Tian-tian Liu +8 位作者 Yan-ling Zhao Wen-jun Zou Jia-bo Wang Shu-xian Liu Zhi-yong Sun Rui-sheng Li Xu Zhou Man Gong Rui-lin Wang 《Chinese Herbal Medicines》 CAS 2014年第1期29-35,共7页
Objective To explore the active components with toxic effects in five Aconitum L. herbal medicines on Tetrahymena thermophila. Methods The fingerprints of five Aconitum L. herbal medicines were established by ultra-hi... Objective To explore the active components with toxic effects in five Aconitum L. herbal medicines on Tetrahymena thermophila. Methods The fingerprints of five Aconitum L. herbal medicines were established by ultra-high performance liquid chromatography (UPLC) and the toxicity was evaluated by using a TAM Air Isothermal Calorimeter on Tetrahymena thermophila SB1 10. Results By analyzing the spectrum- effect relationships between UPLC fingerprints and toxic effects, the active components which had the toxic effects were obtained. Conclusion This work provides a general model of the combination of UPLC and microcalorimetry to study the spectrum-effect relationships of the five Aconitum L. herbal medicines, which could be used to evaluate the toxic effects and analyze the principal toxic components of the five Aconitum L. herbal medicines. On the whole, this result provides the experimental basis for the safe use of the five Aconitum L. herbal medicines in clinic. 展开更多
关键词 Aconitum L. herbal medicines MICROCALORIMETRY spectrum-effect relationships Tetrahymena thermophila ultra-high performance liquid chromatography
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The completed macronuclear genome of a model ciliate Tetrahymena thermophila and its application in genome scrambling and copy number analyses 被引量:4
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作者 Yalan Sheng Lili Duan +3 位作者 Ting Cheng Yu Qiao Naomi AStover Shan Gao 《Science China(Life Sciences)》 SCIE CAS CSCD 2020年第10期1534-1542,共9页
The ciliate Tetrahymena thermophila has been a powerful model system for molecular and cellular biology.However,some investigations have been limited due to the incomplete closure and sequencing of the macronuclear ge... The ciliate Tetrahymena thermophila has been a powerful model system for molecular and cellular biology.However,some investigations have been limited due to the incomplete closure and sequencing of the macronuclear genome assembly,which for many years has been stalled at 1,158 scaffolds,with large sections of unknown sequences(available in Tetrahymena Genome Database,TGD,http://ciliate.org/).Here we completed the first chromosome-level Tetrahymena macronuclear genome assembly,with approximately 300×long Single Molecule,Real-Time reads of the wild-type SB210 cells—the reference strain for the initial macronuclear genome sequencing project.All 181 chromosomes were capped with two telomeres and gaps were entirely closed.The completed genome shows significant improvements over the current assembly(TGD 2014)in both chromosome structure and sequence integrity.The majority of previously identified gene models shown in TGD were retained,with the addition of 36 new genes and 883 genes with modified gene models.The new genome and annotation were incorporated into TGD.This new genome allows for pursuit in some underexplored areas that were far more challenging previously;two of them,genome scrambling and chromosomal copy number,were investigated in this study.We expect that the completed macronuclear genome will facilitate many studies in Tetrahymena biology,as well as multiple lines of research in other eukaryotes. 展开更多
关键词 Tetrahymena thermophila macronuclear genome 181 chromosomes DNA scrambling copy number
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Microcalorimetric Investigation of Toxic Effects of Three Injectable Solubilizing Excipients on Tetrahymena thermophila BF5 Growth 被引量:1
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作者 鄢丹 张少锋 +3 位作者 韩玉梅 杨明 齐云 肖小河 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2011年第5期871-876,共6页
Using microcalorimetry, thermal metabolic curves of Tetrahymena thermophila BF5 (T. thermophila BFs) growth at 28℃ affected by three injectable solubilizing excipients (ISE) including tween 80, hydroxypro- pyl-β... Using microcalorimetry, thermal metabolic curves of Tetrahymena thermophila BF5 (T. thermophila BFs) growth at 28℃ affected by three injectable solubilizing excipients (ISE) including tween 80, hydroxypro- pyl-β-cyclodextrin (HP-β-CD) and poloxamer 188 were measured. Meanwhile, the toxicities of three ISE were evaluated by dynamic parameters of thermal metabolic curves. In addition, the irritative effects of the ISE on myoblast L6cells were investigated to show their cytotoxicities by biochemical method. The results indicated that the effects of the ISE on T. thermophila BF5 varied for different ISE. 5% inhibition concentration values (IC5) of the ISE were 1.33, 1.83 and 1.64 mg/mL for tween 80, HP-β-CD and poloxamer 188, respectively. By the principal component analysis (PCA), the total quantity of heat (Q), growth rate constant (k) and second maximum power (P2) were selected as the main characteristic parameters to present their toxicities, there were good linear relationships between Q, k, P2 and concentrations c, suggesting that the toxicities of the ISE on T. thermophila BF5 were closely linked to their concentrations. The results of creatine kinase (CK) bioassay of myoblast L6 cells indicated that the sequence of irritative effects of the ISE was HP-β-CD〈poloxamer 188〈tween 80, which added to the results ob- tained from microcalorimetry. 展开更多
关键词 CALORIMETRY Tetrahymena thermophila BFs injectable solubilizing excipient creatine kinase biosaaay cytotoxicity
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The toxic effect of solubilizing excipients on Tetrahymena thermophila BF_5 growth investigated by microcalorimetry 被引量:4
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作者 ZHANG ShaoFeng YAN Dan +3 位作者 TANG HuiYing YANG Ming WANG YueSheng XIAO XiaoHe 《Chinese Science Bulletin》 SCIE EI CAS 2010年第18期1870-1876,共7页
The toxic effect of different solubilizing excipients on the growth and metabolism of Tetrahymena thermophila BF5(T.t.BF5) at various concentrations was investigated by microcalorimetry.The thermogenic curves of T.t.B... The toxic effect of different solubilizing excipients on the growth and metabolism of Tetrahymena thermophila BF5(T.t.BF5) at various concentrations was investigated by microcalorimetry.The thermogenic curves of T.t.BF5 growth were determined at 28°C,and were evaluated by dynamic parameters.The results indicated that the values of growth rate constant(k),maximum power(P1,P2),peak time(T1,T2) and total quantity of heat(Q) varied for different excipients.There was a good linear relationship between k and concentrations(r>0.95,P<0.01).5% inhibition concentration(IC5) of poloxamer 188,Tween 80,PEG 600,PEG 400 and Tween 20 was 2.18,1.07,1.35,0.58,and 0.045 mg/mL,respectively.After the principal component analysis(PCA),Q,k and P1 could characterize the effect of these excipients on T.t.BF5 growth.Comprehensive evaluation indicated that compared with the control group,poloxamer 188 had the weakest toxicity and Tween 20 had the strongest toxicity. 展开更多
关键词 生长速率常数 嗜热四膜虫 毒性作用 辅料 聚乙二醇400 微量热 抑制浓度 RAMP
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副溶血弧菌hemoD敲除菌株构建及致病力评估
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作者 胡少杰 车金远 +2 位作者 房启童 罗土炎 鲍宝龙 《上海海洋大学学报》 北大核心 2025年第3期686-695,共10页
通过同源重组技术,构建了hemoD基因缺失的副溶血弧菌敲除菌株ΔhemoD,对ΔhemoD菌株的毒力和感染四膜虫及凡纳滨对虾(Penaeus vannamei)的能力进行了评估。相比野生型菌株,ΔhemoD菌株溶血活性下降了45.7%,生物膜形成能力下降了36.2%,... 通过同源重组技术,构建了hemoD基因缺失的副溶血弧菌敲除菌株ΔhemoD,对ΔhemoD菌株的毒力和感染四膜虫及凡纳滨对虾(Penaeus vannamei)的能力进行了评估。相比野生型菌株,ΔhemoD菌株溶血活性下降了45.7%,生物膜形成能力下降了36.2%,生长无明显变化。相比野生型菌株,ΔhemoD菌株对四膜虫的毒力降低,四膜虫对ΔhemoD菌株具有更强的摄食能力,增殖能力也更强。针对凡纳滨对虾的攻毒实验,发现ΔhemoD菌株半数致死量为1.3×10^(8) cfu/mL,相较于野生型菌株提高了5.06倍,ΔhemoD菌株定殖凡纳滨对虾肠道能力明显下降。病理切片结果显示,ΔhemoD菌株对肝胰腺的损伤能力相较于野生菌株也有所下降,肝胰腺细胞溶解及空泡化现象较轻微。这些研究结果表明,ΔhemoD菌株的毒性明显减弱,对四膜虫和凡纳滨对虾的致病力明显减弱,是一株减毒的副溶血弧菌菌株,为后续进一步开发副溶血弧菌减毒疫苗奠定基础。 展开更多
关键词 副溶血弧菌 hemoD基因 四膜虫 凡纳滨对虾 致病力
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不同填埋时间、不同季节的垃圾渗滤液生物毒性 被引量:15
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作者 刘婷 陈朱蕾 +2 位作者 唐素琴 谢文刚 杨列 《环境科学》 EI CAS CSCD 北大核心 2010年第2期541-546,共6页
以武汉市7个城市生活垃圾填埋场渗滤液作为研究对象,探讨不同填埋时间、不同季节渗滤液的生物毒性变化以及理化指标与生物毒性效应的相关性.毒性实验采用嗜热四膜虫(Tetrahymena thermophila)作为试验生物,进行了渗滤液对受试生物... 以武汉市7个城市生活垃圾填埋场渗滤液作为研究对象,探讨不同填埋时间、不同季节渗滤液的生物毒性变化以及理化指标与生物毒性效应的相关性.毒性实验采用嗜热四膜虫(Tetrahymena thermophila)作为试验生物,进行了渗滤液对受试生物的24h半数致死浓度LC50和生长抑制测定.结果表明,不同填埋时间的渗滤液LC50在0.84%~12.15%之间;随着填埋时间延长,渗滤液LC50有增大的趋势,急性毒性逐渐减小,但渗滤液对嗜热四膜虫种群的生长抑制没有减少的趋势.不同季节渗滤液的LC50没有明显的规律性,夏季的渗滤液LC50较小,急性毒性较强;不同季节的渗滤液对嗜热四膜虫的生长抑制情况不同,春季渗滤液的生长抑制作用最小.渗滤液理化指标与LC50无显著相关性,而渗滤液对嗜热四膜虫种群的生长抑制作用随着COD、BOD5、NH4^+—N和邻苯二甲酸二异辛酯(DEHP)的增加而增强. 展开更多
关键词 填埋时间 季节 垃圾渗滤液 嗜热四膜虫 毒性
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嗜热拟青霉固体发酵产木聚糖酶条件的优化 被引量:16
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作者 杨绍青 闫巧娟 +2 位作者 江正强 李里特 王有智 《微生物学通报》 CAS CSCD 北大核心 2006年第3期1-6,共6页
从土壤中筛选出一株高产木聚糖酶的嗜热真菌J18,经鉴定为一种新的拟青霉,暂定为嗜热拟青霉。该菌能够利用几种天然纤维质材料固体发酵产木聚糖酶,小麦秸杆为最佳碳源。单因素优化试验表明:小麦秸杆粒度为0.3 mm~0.45 mm,初始水分含... 从土壤中筛选出一株高产木聚糖酶的嗜热真菌J18,经鉴定为一种新的拟青霉,暂定为嗜热拟青霉。该菌能够利用几种天然纤维质材料固体发酵产木聚糖酶,小麦秸杆为最佳碳源。单因素优化试验表明:小麦秸杆粒度为0.3 mm~0.45 mm,初始水分含量83%,初始pH 7.0,温度为50℃为最佳产酶条件。在优化后的条件下,培养8 d产木聚糖酶的水平高达18,580 U/g干基碳源。因此,嗜热拟青霉固体发酵产木聚糖酶将具有很大的工业化应用前景。 展开更多
关键词 嗜热拟青霉 木聚糖酶 固体发酵 小麦秸杆
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四膜虫彗星实验在环境水质检测中的应用 被引量:16
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作者 王丽 鲁志松 +1 位作者 丁书茂 杨旭 《环境科学与技术》 CAS CSCD 北大核心 2006年第5期31-33,共3页
介绍四膜虫作为生物材料在彗星实验水质检测中的应用,探讨了将单细胞原生生物应用于彗星实验在环境水质检测、遗传毒性检测等方面的应用优势和发展前景。研究结果表明:过氧化氢浓度与细胞损伤之间呈现良好的剂量-效应关系,东湖水和长江... 介绍四膜虫作为生物材料在彗星实验水质检测中的应用,探讨了将单细胞原生生物应用于彗星实验在环境水质检测、遗传毒性检测等方面的应用优势和发展前景。研究结果表明:过氧化氢浓度与细胞损伤之间呈现良好的剂量-效应关系,东湖水和长江水未造成四膜虫DNA的损伤,印染厂污水对细胞有严重的损伤作用,可能会影响正常的生态环境。 展开更多
关键词 分子生物学 彗星实验 原生生物 四膜虫 水质检测
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定向进化提高嗜热拟青霉J18耐热β-1,3-1,4-葡聚糖酶在酸性条件下的催化能力 被引量:10
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作者 李一男 贾会勇 +2 位作者 闫巧娟 江正强 杨绍青 《生物工程学报》 CAS CSCD 北大核心 2011年第12期1797-1804,共8页
应用定向进化技术提高了嗜热拟青霉Paecilomyces thermophila J18耐热β-1,3-1,4-葡聚糖酶(PtLic16A)在酸性条件下的催化能力。结合易错PCR和DNA改组的方法,构建了β-葡聚糖酶的突变体文库;利用刚果红染色法建立了阳性克隆的高通量筛选... 应用定向进化技术提高了嗜热拟青霉Paecilomyces thermophila J18耐热β-1,3-1,4-葡聚糖酶(PtLic16A)在酸性条件下的催化能力。结合易错PCR和DNA改组的方法,构建了β-葡聚糖酶的突变体文库;利用刚果红染色法建立了阳性克隆的高通量筛选体系。筛选得到的突变酶PtLic16AM1的反应最适pH由7.0变化至5.5,且保持了原有的耐热性和比酶活。突变酶的DNA序列中有4个点位发生突变,引发了4处氨基酸替换,分别是T58S、Y110N、G195E和D221G。结构模拟结果显示,发生突变的4个氨基酸位点中,Y110N位置靠近酶活性中心,而T58S、G195E和D221G则离酶活性中心较远,其中T58S、G195E可能对酶最适pH的变化起到了关键作用。 展开更多
关键词 嗜热拟青霉 β-1 3.1 4.葡聚糖酶 易错PCR DNA改组
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含氮杂环化合物对四膜虫的毒性作用研究 被引量:10
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作者 徐忠东 施荣华 +1 位作者 耿明 陶瑞松 《中国农业大学学报》 CAS CSCD 北大核心 2008年第3期57-62,共6页
从DNA损伤角度探讨吲哚、吡啶、喹啉和异喹啉4种工业废水中常见的含氮杂环化合物对模式材料四膜虫的毒性作用。采用单细胞凝胶电泳技术(SCGE)和流式细胞术2种快速而灵敏的检测方法联合检测,以四膜虫的彗尾长度、拖尾率、细胞损伤率、DN... 从DNA损伤角度探讨吲哚、吡啶、喹啉和异喹啉4种工业废水中常见的含氮杂环化合物对模式材料四膜虫的毒性作用。采用单细胞凝胶电泳技术(SCGE)和流式细胞术2种快速而灵敏的检测方法联合检测,以四膜虫的彗尾长度、拖尾率、细胞损伤率、DNA损伤专用单位以及DNA相对荧光强度为指标,研究以上4种含氮杂环化合物引起四膜虫核DNA损伤而表现的毒性作用。单细胞凝胶电泳检测表明:四膜虫经4种含氮杂环化合物在不同质量浓度(5和50 mg/L)条件下染毒后彗尾长度、DNA损伤专用单位与阴性对照组比较,有显著差异(P<0.01)。吲哚处理组与吡啶处理组同浓度比较,P>0.05,差异不显著;与喹啉、异喹啉处理组同浓度比较,P<0.01,差异显著。吡啶处理组与喹啉、异喹啉处理组相同质量浓度比较,P<0.01,差异显著。喹啉处理组与异喹啉处理组低质量浓度比较差异不显著,高质量浓度比较则差异显著。流式细胞实验表明:2种质量浓度处理组DNA相对荧光强度低的细胞数比对照组明显增加,4种含氮杂环化合物均表现出较强毒性,毒性大小由强到弱依次为异喹啉、喹啉、吲哚、吡啶。 展开更多
关键词 含氮杂环化合物 毒性 四膜虫 DNA损伤 单细胞凝胶电泳 流式细胞术
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镉和铜对嗜热四膜虫金属硫蛋白基因的诱导表达 被引量:8
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作者 俞婷 缪炜 +2 位作者 万明亮 沈韫芬 傅诚杰 《动物学报》 SCIE CAS CSCD 北大核心 2005年第6期1115-1121,共7页
本文在荧光定量PCR优化的基础上,利用该技术考察了不同浓度的重金属镉和铜对嗜热四膜虫金属硫蛋白基因(MTT1)诱导表达的变化规律。结果表明MTT1基因的表达对镉离子的诱导更灵敏,且在一定阈值浓度(≤35.2μmol/L)范围内,镉离子浓度升高... 本文在荧光定量PCR优化的基础上,利用该技术考察了不同浓度的重金属镉和铜对嗜热四膜虫金属硫蛋白基因(MTT1)诱导表达的变化规律。结果表明MTT1基因的表达对镉离子的诱导更灵敏,且在一定阈值浓度(≤35.2μmol/L)范围内,镉离子浓度升高会增加MTT1基因表达量,超过该阈值后表达量迅速下降;镉与铜同时诱导时MTT1基因的表达情况与镉单独诱导的类似,但阈值浓度减小为22μmol/L,表明二者的联合毒性为协同作用。镉离子浓度低于22μmol/L时,与铜离子的共同作用会大大增加MTT1基因的表达量,从而增强了四膜虫的解毒能力。 展开更多
关键词 嗜热四膜虫 金属硫蛋白基因 实时荧光定量PCR
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