CURRENT MICROBIOLOGY
·
2014
·Vol. 70
·期 1
·27-34
·
IF 1.359
Wang Shuzhi,Pan Xiangliang,Zhang Daoyong
The
knowledge of the effects of Sb(V) on the physiological characteristics of cyanobacteria was still limited. In the present study, responses of photosystem I and II (PSI and PSII), cyclic electron flow (CEF), and interphotosystem electron transport of Microcystis aeruginosa to 5–100 mg/l Sb(V) were synchronously measured using the Dual-PAM-100. 5 mg/l Sb (V) significantly inhibited PSII activity, but had no significant effects on PSI activity. At higher concentrations of Sb(V), the quantum yield and electron transport of PSI were less affected compared to PSII. The ratio of Y (II)/ Y (I) significantly decreased with increasing Sb(V) concentration. It decreased from 0.7 for control to 0.4 for 100 mg/l Sb(V)-treated cells, indicating that the change of the distribution of quantum yields between two photosystems and more serious inhibition of PSII under stress of Sb(V) compared to PSI. CEF was activated associated with the inhibition of linear electron flow after exposure to Sb(V). The contribution of Y (CEF) to the quantum yield and activity of PSI increased with increasing Sb(V) concentrations. The cyclic electron transport rate made a significant contribution to electron transport rate of PSI, especially at high Sb(V) concentration (100 mg/l) and high illumination (above 555 μmol photons/m 2 /s). The stimulation of CEF was essential for the higher tolerance of PSI than PSII to Sb(V).
研究领域:
植物学
·
环境科学
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DOI
PubMed
高影响因子
MOLECULES
·
2018
·Vol. 23
·期 5
·1105
·
IF 3.098
Wei Yang,Xiangyang Lei,Haohao Hui,Qinghua Zhang,Xueran Deng
Moisture-resistant silicone coatings were prepared on the surface of potassium dihydrogen phosphate (KDP) crystal by means of spin-coating, in which hydrophobic-modified SiO2nanoparticles were embedded in a certain proportion. The refractive index of such coating can be tuned arbitrarily in the range of 1.21–1.44, which endows the KDP optical component with excellent transmission capability as well as the moisture proof effect. A dual-layer anti-reflective coating system was obtained by covering this silicone coating with a porous SiO2coating which is specially treated to enhance the moisture resistance. Transmittance of such a dual-layer coating system could reach 99.60% and 99.62% at 1064 nm and 532 nm, respectively, by precisely matching the refractive index of both layers. Furthermore, the long-term stability of this coating system has been verified at high humidity ambient of 80% RH for 27 weeks.Keywords:moisture-resistant;refractive index tunable;high-power laser system
研究领域:
光学材料
·
涂层技术
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DOI
PubMed
高影响因子
JOURNAL OF LUMINESCENCE
·
2022
·
IF 4.171
Hongyang Wang,Yu Zhang,Shuai Lan,Lei Cao,Fei Peng,Dandan Jia,Dongjun Wang
The green fluorescent protein (GFP) shows a vivid model to design and fabricate fluorescent materials, however, a simple and generic strategy has not been really achieved to mimic the GFP system. Here we report a strategy to prepare nanoscale micelles acting like the “nano-can” in GFP, enabling a group of non-luminous amines to fluoresce. The fluorescent systems can be fabricated by mixing two kinds of commercially available non-conjugated precursors, one is amphiphilic ring-type compound for micelle, the other is amine for chromophore . Our results suggest that the nanoscale micelles provide ideal confined domains, within which amine compounds can form effective chromophores. The micelle-triggered method is generalizable to various kinds of precursors, and the emission can be tuned at different colors upon altering precursors. The presented strategy will be a starting point for a new luminescent research area in which we pay more attention on the environment than chromophore.
研究领域:
生物化学
·
材料科学
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DOI
高影响因子
JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY
·
2021
·
IF 5.279
Yanjing Guo,Weizhe Liu,He Wang,Xiaoxiong Wang,Sheng Qiang,Hazem M. Kalaji,Reto Jörg Strasser,Shiguo Chen
A biocontrol method plays an important role in weed management. In this study, we aimed to clarify the phytotoxicity of the mycotoxin patulin (PAT) and reveal its mode of action as a new natural photosystem II (PSII) inhibitor. Phytotoxicity test showed that PAT has herbicidal activity and causes significant leaf lesions on Ageratina adenophora. Under a half-inhibition concentration I50 (2.24 μM), the observed significant decrease in oxygen evolution rate and the increase in the J-step of the chlorophyll fluorescence rise OJIP curve indicated that PAT strongly reduces photosynthetic efficiency by blocking electron transport from the primary to secondary plastoquinone acceptors (QA to QB) of PSII. Molecular modeling of PAT docking to the A. adenophora D1 protein suggested that PAT bounds to the QB site by forming hydrogen bonds to histidine 252 in the D1 protein. It is proposed that PAT is a new natural PSII inhibitor and has the potential to be developed into a bioherbicide or used as a template scaffold for discovering novel derivatives with more potent herbicidal activity.
研究领域:
植物学
·
分子生物学
·
农业科学
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DOI
高影响因子
CURRENT MICROBIOLOGY
·
2012
·Vol. 65
·期 6
·733-741
·
IF 1.815
Wang Shuzhi,Pan Xiangliang
In this study, effects of antimony Sb(V) on growth, pigments content, oxygen evolution, and photosystem II (PSII) activity of Microcystis aeruginosa were investigated. JIP-test, Q
− A
reoxidation kinetic test and S-state test were used in this study to study the energy distribution and electron transport in PSII. Treatment with Sb(V) at various concentrations ranging from 5 to 100 mg/l had long-term effects on growth, pigments content, and oxygen evolution of M . aeruginosa . Low concentration of Sb(V) had no significant inhibition of the biomass production and PSII activity but inhibited the pigment synthesis. Growth, pigments content, oxygen evolution, and PSII activity were seriously inhibited when treated by high concentration of Sb(V) (100 mg/l). The target sites of Sb(V) toxic effect on the PSII of M . aeruginosa were mainly on the donor side and the apparatus in the light-dependent reaction. The quantum yield for photochemistry, density of reaction centers and photosynthesis performance index decreased, whereas the dissipated energy increased. PSII activity of M . aeruginosa was promoted when exposure to 50 mg/l Sb(V) by increasing the density of active reaction centers and electron transport after Q
− A
.
研究领域:
环境科学
·
微生物学
·
植物生理学
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产品关联
DOI
PubMed
高影响因子
Marine Drugs
·
2021
·Vol. 19
·期 6
·336
·
IF 5.118
Ni Wu,Mengmeng Tong,Siyu Gou,Weiji Zeng,Zhuoyun Xu,Tianjiu Jiang
Chattonellaspecies,C. marinaandC. ovata, are harmful raphidophycean flagellates known to have hemolytic effects on many marine organisms and resulting in massive ecological damage worldwide. However, knowledge of the toxigenic mechanism of these ichthyotoxic flagellates is still limited. Light was reported to be responsible for the hemolytic activity (HA) ofChattonellaspecies. Therefore, the response of photoprotective, photosynthetic accessory pigments, the photosystem II (PSII) electron transport chain, as well as HA were investigated in non-axenicC. marinaandC. ovatacultures under variable environmental conditions (light, iron and addition of photosynthetic inhibitors). HA and hydrogen peroxide (H2O2) were quantified using erythrocytes and pHPA assay. Results confirmed that% HA ofChattonellawas initiated by light, but was not always elicited during cell division. Exponential growth ofC. marinaandC. ovataunder the light over 100 µmol m−2s−1or iron-sufficient conditions elicited high hemolytic activity. Inhibitors of PSII reduced the HA ofC. marina, but had no effect onC. ovata. The toxicological response indicated that HA inChattonellawas not associated with the photoprotective system, i.e., xanthophyll cycle and regulation of reactive oxygen species, nor the PSII electron transport chain, but most likely occurred during energy transport through the light-harvesting antenna pigments. A positive, highly significant relationship between HA and chlorophyll (chl) biosynthesis pigments, especially chlc2and chla, in both species, indicated that hemolytic toxin may be generated during electron/energy transfer through the chlc2biosynthesis pathway.Keywords:Chattonella marina;Chattonella ovata;hemolytic activity;photosystem II;hydrogen peroxide;chlorophyllc2
研究领域:
生物学
·
生态学
·
毒理学
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DOI
PubMed
高影响因子
SCIENCE OF THE TOTAL ENVIRONMENT
·
2022
·
IF 10.753
Zhiheng Li,Jiazheng Chen,Jie Chen,Jiaojun Jin,Hanmei Chen,Huijun Liu
Due to the persistence of ionic liquids (ILs) in aquatic environments, it is necessary to reveal their ecological risk to aquatic organisms. Herein, the biotoxicity of two alkyl-methylimidazolium nitrate ILs ([C 10 mim]NO 3 and [C 12 mim]NO 3 ) against Scenedesmus obliquus were studied. Results showed that the growth inhibition of S. obliquus increased with increasing concentrations of ILs, maximum values of 94.61% at 4 mg/L of [C 10 mim]NO 3 and 97.34% at 0.8 mg/L of [C 12 min]NO 3 were observed. The fluorescence parameters of photosystem II, such as light quantum yield and electron transfer rate, showed a negative relationship with the exposure dose. [C 12 mim]NO 3 had a more significant effect than [C 10 mim]NO 3 . Moreover, the redox homeostasis of algae was disrupted; the accumulation of reactive oxygen species , leading to obvious inhibition of superoxide dismutase and catalase activities was observed. A metabolomic analysis indicated that the contents of most metabolites were reduced significantly, and fructose and galactose decreased significantly by 42.3% and 88.6%, respectively, in the [C 10 mim]NO 3 treatment compared to those in the control. The inhibition of amino acid biosynthesis and glyoxylate and dicarboxylate metabolism explained the more serious biotoxicity of [C 12 mim]NO 3 than that of [C 10 mim]NO 3 . This study facilitates a better understanding of the environmental safety and ecological risks of ILs.
研究领域:
环境科学
·
植物生理学
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产品关联
DOI
PubMed
高影响因子
PEST MANAGEMENT SCIENCE
·
2023
·Vol. 80
·期 1
·133-148
·
IF 4.1
Qian Yang,Yanjing Guo,He Wang,Zhi Luo,Ying Chen,Mengyun Jiang,Huan Lu,Bernal E. Valverde,Sheng Qiang,Reto Jörg Strasser,Shiguo Chen
BACKGROUND Bioherbicides are becoming more attractive as safe weed control tools towards sustainable agriculture. Natural products constitute an important source chemicals and chemical leads for discovery and development of novel pesticide target sites. Citrinin is a bioactive compound produced by fungi of the genera Penicillium and Aspergillus . However, its physiological-biochemical mechanism as a phytotoxin remains unclear. RESULTS Citrinin causes visible leaf lesions on Ageratina adenophora similar to those produced by the commercial herbicide bromoxynil. Phytotoxicity bioassay tests using 24 plant species confirmed that citrinin has a broad activity spectrum and therefore has potential as a bioherbicide. Based on chlorophyll fluorescence studies, citrinin mainly blocks PSII electron flow beyond plastoquinone Q A at the acceptor side, resulting in the inactivation of PSII reaction centers. Furthermore, molecular modeling of citrinin docking to the A. adenophora D1 protein suggests that it binds to the plastoquinone Q B site by a hydrogen bond between the O1 hydroxy oxygen atom of citrinin and the histidine 215 of the D1 protein, the same way as classical phenolic PSII herbicides do. Finally, 32 new citrinin derivatives were designed and sorted according to free energies on the basis of the molecular model of an interaction between the citrinin molecule and the D1 protein. Five of the modeled compounds had much higher ligand binding affinity within the D1 protein compared with lead compound citrinin. CONCLUSION Citrinin is a novel natural PSII inhibitor that has the potential to be developed into a bioherbicide or utilized as a lead compound for discovery of new derivatives with high herbicidal potency. © 2023 Society of Chemical Industry.
研究领域:
植物学
·
农业科学
·
分子生物学
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DOI
PubMed
高影响因子
Applied Sciences-Basel
·
2019
·Vol. 9
·期 23
·5038
·
IF 2.217
Xue-Ran Deng,Wei Yang,Hao-Hao Hui,Qing-Hua Zhang,Qiao Xu,Jin-Ju Chen,Ji-Liang Zhu,Xiang-Yang Lei
A high-power laser system is employed to drive the fusion ignition to realize sustainable supply of green energy according to the inertial confinement fusion theory, in which frequency-converting crystals are sealed in the terminal vacuum chamber and utilized to turn the incident laser (1053 nm) to the desired one (351 nm). However, the reflected 351 nm laser from the pellet hohlraum that goes back through the frequency-converting crystal is found to be harmful for the upstream elements that are located before the terminal chamber. In this study, a specialized coating system for the frequency-converting crystals was designed and fabricated to both ensure high output power for the fusion and reduce the reflected 351 nm laser energy by absorption. Furthermore, the structural, mechanical, and laser-damage resistant properties of this coating were investigated as well.Keywords:high-power laser system;frequency-converting crystal coating;reflected 351 nm laser
研究领域:
光学材料
·
激光技术
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产品关联
DOI
高影响因子
SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY
·
2020
·
IF 3.232
Jin Yang,Yan Cao,Naidong Zhang
A method was developed that used hydroxylamine hydrochloride as a probe in a superoxide anion radical-generating visible light system for determining superoxide anion radicals. An Azure I solution with hydroxylamine hydrochloride was illuminated, after which a ferric iron solution was added to the sample solution and the remaining hydroxylamine hydrochloride in solution reduced from ferric to ferrous ions. Then, 1,10-phenanthroline solution was added and spectrophotometrically measured at 510 nm, which indirectly indicated the hydroxylamine hydrochloride content. The yields of superoxide anion radicals were indirectly expressed by the hydroxylamine hydrochloride decrement. Under optimal experimental conditions, the linear range was 0.0–1.5 × 10 −5 M and the limit of detection and limit of quantification were obtained to be 8.37 × 10 −7 and 2.54 × 10 −6 M with an R 2 of 0.9993. The method was simple and feasible and could be used for the stable measurement of superoxide anion radicals produced by photosensitizers that produce color under acidic conditions in visible light systems.
研究领域:
生物化学
·
分析化学
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产品关联
DOI
PubMed
高影响因子
PHYCOLOGIA
·
2015
·
IF 1.915
Rui Liu,Xiaofei Ran,Fang Bai,Jinzhu Xu,Songqi Yang,Junqiong Shi,Zhongxing Wu
In order to investigate the toxicity targets of the secondary metabolite from aquatic plants, N-phenyl-2-naphthylamine, on Cylindrospermopsis raciborskii photosynthetic system II (PSII), we determined chlorophyll a (Chl a), specific growth rate (μ−d), photosynthetic rapid light curves and polyphasic Chl a fluorescence transients following exposure to N-phenyl-2-naphthylamine. The results showed significant decreases in Chl a following 48 h at high concentration (0.50 mg l−1) exposure to N-phenyl-2-naphthylamine. The PSII electron transfer rate and Chl a fluorescence transients appeared to be affected after the cells were exposed to concentrations of 0.50, 1.00 and 2.00 mg l−1. Exposure to higher concentration of N-phenyl-2-naphthylamine (> 0.50 mg l−1) mainly depressed the density of reaction centers (RC/CS0) and quantum energy flux ratios (ϕP0 and ϕE0) but increased the absorption flux per RC (ABS/RC), dissipated energy flux per RC (DI0/RC) and the average redox state of QA−/QA in the time span from 0 to tFmax (Sm/tFmax). However, exposure to low concentration (≤ 0.5 mg l−1) mainly inhibited the trapping energy fluxes per reaction center (TR0/RC), electron transport energy fluxes per reaction center (ET0/RC) and energy flux ratio (ψ0). This suggested that the donor and the acceptor sides of PSII were targets of N-phenyl-2-naphthylamine in C. raciborskii. Additionally, our results indicated that the toxicity target at low concentrations of N-phenyl-2-naphthylamine was at each step of electron transport between QA− and the Cyt b6/f complex; whereas, the reduction of QA was the potential target at high concentrations. We suggest that N-phenyl-2-naphthylamine may be a potential allelochemical to control harmful cyanobacterial blooms.
研究领域:
水生生物学
·
环境科学
·
植物生理学
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产品关联
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2018
·
IF 8.097
Shiliang Mei,Xiaoyan Liu,Wanlu Zhang,Ran Liu,Lirong Zheng,Ruiqian Guo,Pengfei Tian
This work proposes a high-bandwidth white-light system consisting of a blue gallium nitride (GaN) micro-LED (μLED) exciting yellow-emitting CsPbBr1.8I1.2 perovskite quantum dots (YQDs) for high-speed real-time visible light communication (VLC). The packaged 80 μm × 80 μm blue-emitting μLED has a modulation bandwidth of ∼160 MHz and a peak emission wavelength of ∼445 nm. The achievable bandwidth of the white-light system is up to 85 MHz in the absence of filters and equalization technology. Meanwhile, the bandwidth of the YQDs as a color converter is as high as 73 MHz with the blue GaN μLED as the pump source. A maximum data rate of 300 Mbps can be achieved by taking advantage of the high bandwidth of the white-light system using the non-return-to-zero on–off keying (NRZ-OOK) modulation scheme. The resultant bit-error rate is 2.0 × 10–3, well beneath the forward error correction criterion of 3.8 × 10–3 required for error-free data transmission. In addition, the YQDs which we proposed as a color converter possess high stability for VLC. After half a year, the achievable bandwidths of the white-light system and the YQDs are still up to 83 and 70 MHz, respectively. This study provides the direction of developing high-bandwidth white-light system for both high-efficiency solid-state lighting and high-speed VLC.
研究领域:
光学
·
通信工程
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产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）