AQUATIC TOXICOLOGY
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2025
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IF 4.3
Yao Li,Xiangrui Wang,Dingyuan Liang,Xiaoli Zhao,Zhaomin Dong,Yingchen Bai,Wen-Xiong Wang,Willie J.G.M. Peijnenburg,Ying Wang,Wenhong Fan
To assess the bioaccumulation and toxicity of nanoparticles (NPs), analyzing and modelling the relationship between the size distribution of NPs in organisms and the exposure particle size distribution represents an important challenge. Previous studies mostly focused on the NPs with single size. However, the size distribution of NPs is wide and variable in the natural environment. There is a lack of research on the NPs with mixed sizes. This study investigated the size distribution of three gold (Au) NPs with different sizes and their mixtures within a ciliate Tetrahymena thermophila under the same number concentration of particles. Results revealed that smaller particles tended to aggregate and bioaccumulate more in cells. Using expectation–maximization algorithm, a particle size distribution model of NPs in cells was established. This model effectively simulated the size distribution of NPs with mixed sizes in cells, demonstrating high accuracy with a mean absolute error of < 0.001, a root mean squared error of < 0.001, and a correlation coefficient exceeding 0.98. Experimental results further verified that the model reliably predicted the size distribution of NPs with mixed sizes in cells, and smaller particles accounted for a larger proportion of the size distribution and bioaccumulation. These results demonstrated the importance of particle size and size distribution of NPs in their environmental effects. Models developed here can provide guidance for future evaluation of the environmental risks of NPs mixtures.
研究领域:
环境科学
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毒理学
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DOI
PubMed
高影响因子
ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY
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2021
·
IF 6.291
Mengqi Zheng,Hongjun Han,Chunyan Xu,Zhengwen Zhang,Wencheng Ma
The coal pyrolysis wastewater (CPW) contributed to aquatic environment contamination with amount of aromatic pollutants, and the research on joint toxicity of the mixture of aromatic compounds was vital for environmental protection. By using Tetrahymena thermophile as non-target organism, the joint toxicity of typical nonpolar narcotics and polar narcotics in CPW was investigated. The results demonstrated that the nonpolar narcotics exerted chronic and reversible toxicity by hydrophobicity-based membrane perturbation, while polar narcotics performed acute toxicity by irreversible damage of cells. As the most hydrophobic nonpolar narcotics, indole and naphthalene caused the highest joint toxicity in 24 h with the lowest EC 50mix (24.93 mg/L). For phenolic compounds, the combination of p-cresol and p-nitrophenol also showed the top toxicity (EC 50mix = 10.9 mg/L) with relation to high hydrophobicity, and the joint toxicity was obviously stronger and more acute than that of nonpolar narcotics. Furthermore, by studying the joint toxicity of nonpolar narcotics and polar narcotics, the hydrophobicity-based membrane perturbation was the first step of toxicity effects, and afterwards the acute toxicity induced by electrophilic polar substituents of phenols dominated joint toxicity afterwards. This toxicity investigation was critical for understanding universal and specific effects of CPW to aquatic organisms.
研究领域:
环境科学
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毒理学
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DOI
PubMed
高影响因子
ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY
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2024
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IF 6.2
Wenjun Xiong,Wei Wei,Man He,Bin Hu,Jun Men,Jiawei Tu,Wei Miao
Biomethylation is an effective means of arsenic detoxification by organisms living in aquatic environments. Ciliated protozoa (including Tetrahymena species) play an important role in the biochemical cycles of aquatic ecosystems and have a potential application in arsenic biotransformation. This study compared arsenic tolerance, accumulation, methylation, and efflux in 11 Tetrahymena species. Nineteen arsenite (As(III)) S -adenosylmethionine (SAM) methyltransferase ( arsM ) genes, of which 12 are new discoveries, were identified, and protein sequences were studied. We then constructed recombinant cell lines based on the Tetrahymena thermophila ( T. thermophila ) wild-type SB210 strain and expressed each of the 19 arsM genes under the control of the metal-responsive the MTT1 promoter. In the presence of Cd 2+ and As(V), expression of the arsM genes in the recombinant cell lines was much higher than in the donor species. Evaluation of the recombinant cell line identified one with ultra-high arsenic methylation enzyme activity, significantly higher arsenic methylation capacity and much faster methylation rate than other reported arsenic methylated organisms, which methylated 89% of arsenic within 6.5 h. It also had an excellent capacity for the arsenic detoxification of lake water containing As(V), 56% of arsenic was methylated at 250 μg/L As(V) in 48 h. This study has made a significant contribution to our knowledge on arsenic metabolism in protozoa and demonstrates the great potential to use Tetrahymena species in the arsenic biotransformation of aquatic environments.
研究领域:
环境生物学
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分子生物学
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生态学
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DOI
PubMed
高影响因子
JOURNAL OF HAZARDOUS MATERIALS
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2020
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IF 9.038
Jing Li,Jie Wang,Sen Hou,Yichao Huang,Hexia Chen,Zhiqiang Sun,Da Chen
A number of bisphenol A (BPA) analogues are increasingly used as its industrial alternatives. However, their effects on aquatic organisms at both individual and population levels have not been well understood. In this study, effects of five bisphenol analogues (i.e., BPA, BPAF, BPB, BPE and BPS) were investigated by using the unicellular eukaryote Tetrahymena thermophila as a model organism. All of them inhibited individual growth and population proliferation at a concentration of 2.6 μM or 13.0 μM during the 60-h exposure period, with the population suppression capacify ranked as: BPB > BPA ≈ BPAF > BPE > BPS. These analogues also exhibited chemical-specific disruption of fatty acid profiles in single-cell eukaryotes and the transcriptional levels of enzymes involved in fatty acid metabolism/biosynthesis. For example, exposure to BPA and BPE significantly increased the ratio of saturated fatty acids to unsaturated fatty acids, contrary to the desaturation effects exhibited by BPAF and BPB. Overall, our results clearly indicated that these bisphenol analogues could pose chemical-specific effects on low-trophic level aquatic organisms, particularly disruption of endogenous metabolic balances. Selected analogues (i.e., BPB and BPAF) could result in effects similar to or even greater than that of BPA.
研究领域:
环境科学
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毒理学
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水生生物学
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DOI
PubMed
高影响因子
JOURNAL OF CELLULAR BIOCHEMISTRY
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2021
·Vol. 122
·期 12
·1817-1831
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IF 4.429
Hongrui Lv,Lina Hu,Jing Xu,Tao Bo,Wei Wang
Cysteine is a crucial component for all organisms and plays a critical role in the structure, stability, and catalytic functions of many proteins. Tetrahymena has reverse transsulfuration and de novo pathways for cysteine biosynthesis. Cysteine synthase is involved in the de novo cysteine biosynthesis and catalyzes the production of cysteine from O -acetylserine. The novel cysteine synthase TtCSA2 was identified from Tetrahymena thermophila . The TtCSA2 showed high expression levels at the log-phase and the sexual development stage. The TtCsa2 was localized on the outer mitochondrial membrane throughout different developmental stages. However, the truncated N -terminal signal peptide mutant TtCsa2-ΔN23 was localized into the mitochondria. His-TtCsa2 was expressed in Escherichia coli and purified using affinity chromatography. The His-TtCsa2 showed O -acetylserine sulfhydrylase and serine sulfhydrylase activities. Cysteine and glutathione contents decreased in the csa2 KD mutant. Furthermore, mutant cells were sensitive to cadmium and copper stresses. This study indicated that the TtCSA2 was involved in the cysteine synthesis in mitochondria and related to heavy metal stresses resistance in Tetrahymena .
研究领域:
分子生物学
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生物化学
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细胞生物学
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DOI
PubMed
高影响因子
ENVIRONMENTAL POLLUTION
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2021
·
IF 8.071
Yin Hua Cui,Qing Shan Shi,Dan Dan Zhang,Ling Ling Wang,Jin Feng,Yi Wen Chen,Xiao Bao Xie
Ionic liquids (ILs), also known as green solvents, are widely acknowledged in several fields, such as chemical separation, synthesis, and electrochemistry , owing to their excellent physiochemical properties. However, their poor biodegradability may lead to environmental and health risks, posing a severe threat to humans, thus requiring further research. In this study, the biotoxicities of the imidazolium-based ILs were evaluated in Tetrahymena pyriformis . Moreover, IL detoxification was investigated by addition of glutathione (GSH), cysteine, and nicotinamide adenine dinucleotide (NADH). Reactive oxygen species (ROS) initiated by different IL types caused damage to Tetrahymena , while glutathione, cysteine, and NADH eliminated ROS, achieving the detoxification purposes. Detoxification results showed that NADH exhibited the best detoxification ability, followed by glutathione and cysteine. Finally, RT-PCR results suggested that metallothionein might have participated in IL detoxification.
研究领域:
环境科学
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毒理学
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生物化学
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DOI
PubMed
高影响因子
COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY C-TOXICOLOGY & PHARMACOLOGY
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2025
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IF 4.3
Hongming Tang,Juan Liu,Dong Sheng,Xu Ren,Qinghua Yu,Zhixin Guo,Yunpeng Wu,Yuxiao Liu,Yuehan Xiao,Wei Wang,Shigen Ye,Weijia Zhou
Isobavachalcone (IBC), a bioactive flavonoid derived from Psoralea corylifolia , exhibits potent anti-ciliate activity, but its underlying mechanism remains unclear. Utilizing Tetrahymena thermophila as a model organism, we demonstrated that IBC induces dose-dependent mortality (12 h-IC 50 : 1.39 mg/L) and inhibits growth. Mechanistically, IBC triggers oxidative stress by elevating reactive oxygen species (ROS) and disrupting antioxidant enzymes, including superoxide dismutase (SOD), glutathione peroxidase (GPx) and glutathione (GSH). This disruption leads to membrane damage, as evidenced by lactate dehydrogenase (LDH) leakage and ATPase inhibition, as well as mitochondrial dysfunction. Microscopic examination and staining confirmed that cell death occurs via necrotic cell death rather than apoptosis. Transcriptome analysis revealed key pathways, including peroxisome-mediated oxidation, glutathione metabolism, and ATP-binding cassette (ABC) transporters, further supporting the role of IBC in oxidative and structural disruption. These findings elucidate the anti-ciliate mechanism of IBC, providing valuable insights for developing targeted anti-parasitic agents.
研究领域:
微生物学
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药理学
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分子生物学
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寄生虫学
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氧化应激
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药物作用机制
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DOI
PubMed
高影响因子
SPECTROSCOPY LETTERS
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2013
·
IF 0.667
Xiaoyan Zou,Changping Yu,Hongwu Zhang
The wide application of titanium dioxide nanoparticles (TiO2 NPs) has caused a large number of TiO2 NPs to be released into the water environment without treatment, which would inevitably result in unexpected toxic damage to aquatic animals. The objects of this research were to discuss the toxic effects of TiO2 NPs to Tetrahymena pyriformis (T. pyriformis) under dark and light conditions. The Fourier transform infrared (FTIR) spectra were utilized to investigate the biochemical constituent changes of T. pyriformis under the exposure of TiO2 NPs. The results showed that illumination had little effect on the cell numbers of T. pyriformis after 24 hr exposure at 5 mg/L of TiO2 concentration. However, the cell viability of TiO2 NP–exposed T. pyriformis under light illumination (81.4%) decreased compared with that in the dark environment (96.1%). The FTIR results showed that the typical absorption band of the CH2 asymmetric stretching vibration shifted from 2924.64 to 2925.49 cm−1 in the dark, which indicated an increase in membrane fluidity without illumination. A decreased intensity (p < 0.05) was observed in amide I and amide II from 98.57 ± 9.62 and 41.88 ± 3.63 to 75.65 ± 4.07 and 25.25 ± 1.12 in the irradiated T. pyriformis, respectively, which suggested that the coexistence of TiO2 NPs and light could induce an obvious decrease of protein. In the light condition, the overproduction of ROS led to the breakdown of balance of the oxidative/antioxidative system, resulting in the lipid peroxidation and the death of cells. The results further reveal that TiO2 NPs under light conditions are more toxic than in the dark.
研究领域:
环境科学
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纳米技术
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水生毒理学
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生物化学
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产品关联
DOI
高影响因子
AQUATIC TOXICOLOGY
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2014
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IF 3.513
Xiaoyan Zou,Junpeng Shi,Hongwu Zhang
Due to their bactericidal and photocatalytic characteristics, silver nanoparticles (Ag NPs) and titanium dioxide nanoparticles (TiO 2 NPs) are widely used in the fields of environment and physiology. Once these untreated nanoparticles are released into an aquatic environment and encounter one another, there is more uncertainty about their fate and ecotoxicological risks compared with the single nanoparticles. To expand our knowledge of the health and environmental impacts of nanoparticles, we investigated the possible risk of the co-existence of TiO 2 NPs and Ag NPs in an aquatic environment using ciliated protozoa ( Tetrahymena pyriformis ) as an aquatic animal model. In this study, silver ion (Ag + ) release and physicochemical properties, as well as their effect on oxidative stress biomarkers, were monitored. Continuous illumination (12,000 lx) led to the 20.0% decrease in Ag + release in comparison with dark conditions, while TiO 2 NPs and continuous illumination resulted in decreasing the Ag + concentration to 64.3% in contrast with Ag NPs-only suspensions. Toxicity tests indicated that different illumination modes exerted distinct effects of TiO 2 NPs on the toxicity of Ag NPs: no effects, antagonism and synergism in dark, natural light and continuous light, respectively. In the presence of 1.5 mg/L (18.8 μM) TiO 2 NPs, the toxicity of 1.5 mg/L (13.9 μM) Ag NPs was reduced by 28.7% and increased by 6.93% in natural light and 12,000 lx of continuous light, respectively. After culturing in 12,000 lx continuous light for 24 h, SOD activity of the light control surged to 1.96 times compared to the dark control ( P < 0.001). TiO 2 NPs induced a reduction of CAT activity by an average of (36.1 ± 1.7) % in the light. In the natural light reductions in the toxicity of Ag, NPs decrease Ag + concentrations via adsorption of Ag + onto TiO 2 NPs surfaces. The enhancement of Ag NPs toxicity can contribute to the formation of activated TiO 2 –Ag NPs complexes in continuous light. The existence of TiO 2 NPs in various illumination modes changed the surface chemistry of Ag NPs and then led to different toxicity effects. TiO 2 NPs reduce the environmental risks of Ag NPs in natural light, but in continuous light, TiO 2 NPs enhance the environmental risks of Ag NPs.
研究领域:
环境科学
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纳米技术
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毒理学
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水生生物学
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DOI
PubMed
高影响因子
JOURNAL OF EUKARYOTIC MICROBIOLOGY
·
2020
·Vol. 68
·期 2
·e12834
·
IF 2.143
Hongrui Lv,Jing Xu,Tao Bo,Wei Wang
Cysteine is implicated in important biological processes. It is synthesized through two different pathways. Cystathionine β-synthase and cystathionine γ-lyase participate in the reverse transsulfuration pathway, while serine acetyltransferase and cysteine synthase function in the de novo pathway. Two evolutionarily related pyridoxal 5′-phosphate-dependent enzymes, cystathionine β-synthase TtCBS1 (TTHERM_00558300) and cysteine synthase TtCSA1 (TTHERM_00239430), were identified from a freshwater protozoan Tetrahymena thermophila . TtCbs1 contained the N-terminal heme binding domain, catalytic domain, and C-terminal regulatory domain, whereas TtCsa1 consisted of two α/β domains. The catalytic core of the two enzymes is similar. TtCBS1 and TtCSA1 showed high expression levels in the vegetative growth stage and decreased during the sexual developmental stage. TtCbs1 and TtCsa1 were localized in the cytoplasm throughout different developmental stages. His-TtCbs1 and His-TtCsa1 were expressed and purified in vitro. TtCbs1 catalyzed the canonical reaction with the highest velocity and possessed serine sulfhydrylase activity. TtCsa1 showed cysteine synthase activity with high K m for O-acetylserine and low K m for sulfide and also had serine sulfhydrylase activity toward serine. Both TtCbs1 and TtCsa1 catalyzed hydrogen sulfide producing. TtCBS1 knockdown and TtCSA1 knockout mutants affected cysteine and glutathione synthesis. TtCbs1 and TtCsa1 are involved in cysteine synthesis through two different pathways in T . thermophila .
研究领域:
生物化学
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分子生物学
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微生物学
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细胞生物学
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产品关联
DOI
PubMed
高影响因子
ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY
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2020
·
IF 4.872
Hui Hao,Yao Dang,Sheng Chen,Qian Sun,Ren Kong,Shiyang Cheng,Chunsheng Liu
Triphenyl phosphate (TPHP) is one of the most widely used organophosphate flame retardants (OPFRs) and is frequently detected in a variety of environmental media. Previous studies reported that TPHP had toxic effects on vertebrates, but little toxic information was available in lower trophic aquatic organisms which were more sensitive to the exposure of many toxic substances. In this study, protozoa Tetrahymena thermophila ( T. thermophila ) were exposed to 0, 0.01, 0.17 or 2.35 mg/L TPHP for 5 days to study the effects of sub-chronic exposure on theoretical population, cell viability, cell size and number of cilia. Additionally, the effects of TPHP on gene transcription were assessed by transcriptome sequencing technique (RNA-Seq). Cell viability and number of cilia were significantly reduced in all TPHP exposure groups compared with the control. In addition, exposure to 0.17 or 2.35 mg/L TPHP significantly reduced the theoretical population, circumference and body width, and there was a significant decrease in body length in the 2.35 mg/L exposure group. Comparative transcriptome sequencing identified a total of 4105 up- and 4487 down-regulated genes after exposure to 2.35 mg/L TPHP for 5 days compared with the control. KEGG analysis showed that dysfunction of pathways associated with ribosome, spliceosome, phagosome, proteasome and protein processing in endoplasmic reticulum in this study might be responsible for the toxicity of T. thermophila caused by TPHP. In general, the results indicated that TPHP had an adverse effect on the protozoa T. thermophila .
研究领域:
环境毒理学
·
分子生物学
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水生毒理学
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DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）