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
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
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
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
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 ...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 SB110.Results By analyzing the spectrumeffect 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
基金the Key Scientific Research Projects of Henan Province to College Youth Backbone Teacher(No.2021118)the National Key Research and Development Program of China(No.2021YFE0112000)。
文摘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.
基金supported by the National Natural Science Foundation of China (Nos. 31572253, 31601857, 31702009)the Science Foundation for Youths of Shanxi Province (No. 201801D221241)the Postdoctoral Science Foundation of China (No. 2014M551961)
文摘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.
基金Supported by the Natural Science Foundation of Shandong Province (JQ201706)The Marine S&T Fund of Shandong Province for Pilot National Laboratory for Marine Science and Technology (Qingdao) (2018SDKJ0406-2)+2 种基金Fundamental Research Funds for the Central Universities (201841005)the Blue Life Breakthrough Program of LMBB of Qingdao National Laboratory for Marine Science and Technology (MS2018NO04)and National Institutes of Health (2P40OD010964).
文摘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.
基金supported by the Special Foundation of Research on the Traditional Chinese Medicine Vocation (200708006)National Major Special Foundation for New Key Drug Innovation of China (2009ZX09502-003)Project of National Science & Technology Pillar Program of China in the 11th Five-Year Period (2008B AI55B04)
文摘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.
基金State Natural Science Foundation(81173571)The"Twelfth Five-Year Plan"Foundation of China People’s Liberation Army(CWS11C164)The Major Projects of the National Science and Technology(2012ZX10005010-002-002)
文摘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 SB110.Results By analyzing the spectrumeffect 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.
基金Project supported by the Special Foundation of Research on the Traditional Chinese Medicine Vocation （No. 200708006）, the Special Major Foundation of National New Drug Innovation of China （Nos. 2009ZX09502-003, 2009ZX09308-005）, the Beijing Natural Science Foundation and the Open Research Foundation of State Key Laboratory Breeding Base of Systematic Research, Development and Utilization of Chinese Medicine Re- sources.
