BMC MICROBIOLOGY
·
2016
·Vol. 16
·期 1
·1-11
·
IF 2.581
Wang Dan,Zhu Fengqiu,Wang Qian,Rensing Christopher,Yu Peng,Gong Jing,Wang Gejiao
Background Microbial antimonite [Sb(III)] oxidation converts toxic Sb(III) into less toxic antimonate [Sb(V)] and plays an important role in the biogeochemical Sb cycle. Currently, little is known about the mechanisms underlying bacterial Sb(III) resistance and oxidation. Results In this study, Tn5 transposon mutagenesis was conducted in the Sb(III)-oxidizing strain Pseudomonas stutzeri TS44 to isolate the genes responsible for Sb(III) resistance and oxidation. An insertion mutation into gshA, encoding a glutamate cysteine ligase involved in glutathione biosynthesis, generated a strain called P. stutzeri TS44-gshA 540 . This mutant strain was complemented with a plasmid carrying gshA to generate strain P. stutzeri TS44-gshA-C. The transcription of gshA , the two superoxide dismutase (SOD)-encoding genes sodB and sodC as well as the catalase-encoding gene katE was monitored because gshA -encoded glutamate cysteine ligase is responsible for the biosynthesis of glutathione (GSH) and involved in the cellular stress defense system as are superoxide dismutase and catalase responsible for the conversion of ROS. In addition, the cellular content of total ROS and in particular H 2 O 2 was analyzed. Compared to the wild type P. stutzeri TS44 and TS44-gshA-C, the mutant P. stutzeri TS44-gshA 540 had a lower GSH content and exhibited an increased content of total ROS and H 2 O 2 and increased the Sb(III) oxidation rate. Furthermore, the transcription of sodB , sodC and katE was induced by Sb(III). A positive linear correlation was found between the Sb(III) oxidation rate and the H 2 O 2 content ( R
2 = 0.97), indicating that the accumulated H 2 O 2 is correlated to the increased Sb(III) oxidation rate. Conclusions Based on the results, we propose that a disruption of the pathway involved in ROS-protection allowed H 2 O 2 to accumulate. In addition to the previously reported enzyme mediated Sb(III) oxidation, the mechanism of bacterial oxidation of Sb(III) to Sb(V) includes a non-enzymatic mediated step using H 2 O 2 as the oxidant.
研究领域:
微生物学
·
环境科学
✓ 已验证
DOI
PubMed
高影响因子
Journal of Water Process Engineering
·
2024
·
IF 6.3
Weimin Chen,Renjian Deng,Yilin Chen,Chuang Wang,Baolin Hou,Saijun Zhou,Andrew Hursthouse
Arsenic and antimony removal technology have received significant attention due to their considerable danger to aquatic ecosystems. In this study, we designed HCO–(Fe 3 O 4 ) x adsorbents with substantial functional groups, ample pore spaces, and considerable surface area , specially tailored for the simultaneous adsorption of pentavalent arsenic (As( V )) and pentavalent antimony (Sb(V)). The adsorption performance of HCO–(Fe 3 O 4 ) x was subjected variably to the Ce/Fe molar ratio (CFMR), solution pH, and co-existing anions (SO 4 2− , PO 4 3− , SiO 3 2− ). The affinity order of As(V) and Sb(V) onto HCO–(Fe 3 O 4 ) x in binary systems was pH-dependent. At a pH of 2.0, Sb( V ) exhibited stronger adsorption than As(V), whereas the opposite trend occurred at pH levels above 4.0. Analysis of the kinetic data revealed the pseudo-second-order kinetic model was the most appropriate, indicating that chemical adsorption was the predominant mechanism. Notably, the formation of inner-sphere complexes led to a higher adsorption rate for As( V ) compared to Sb(V), attributed to a lower energy barrier of 0.863 eV, facilitating the breakdown of the Fe O bond in As(V)'s asymmetric tetrahedral structure. Various analyses (FTIR, XRD, and XPS) demonstrated that adsorption mechanisms involved multiple processes like hydrogen bonding , ligand exchange, electrostatic attraction, and complexation. The primary contributions for the adsorption of As( V ) and Sb(V) were the inner-sphere complex of cerium , oxygen and arsenic atoms (Ce O As) and the outer-sphere complex of iron, oxygen and antimony atoms (Fe O Sb), respectively, indicating significant differences in the mechanisms. These findings underscored the potential of HCO–(Fe 3 O 4 ) x in mitigating As( V ) and Sb(V) water pollution, emphasizing its considerable promise as an effective remediation agent.
研究领域:
环境化学
·
水污染治理
·
吸附科学
·
环境功能材料
·
重金属去除
✓ 已验证
DOI
高影响因子
ANALYTICAL LETTERS
·
2021
·
IF 2.329
Zhaoxue Zhang,Yi Lu,Haipu Li,Nan Zhang,Junfei Cao,Bo Qiu,Zhaoguang Yang
The simultaneous separation and determination of inorganic trivalent antimony Sb(III) and pentavalent antimony Sb(V) in plant, soil, and sediment samples was carried out by high performance liquid chromatography – inductively coupled plasma – mass spectrometry (HPLC-ICP-MS). The chromatographic conditions (composition and concentration of competing ion, pH value and flow rate of mobile phase) and the operating parameters for inductively coupled plasma – mass spectrometry were optimized by single factor experiments. The separation of the Sb species was achieved within 6 min using the optimized chromatographic conditions. The detection limits of the method were 0.016 μg/L and 0.021 μg/L for Sb(III) and Sb(V), respectively. The retention times of Sb(V) and Sb(III) were 2.7 min and 4.5 min, respectively. The relative standard deviations for replicate measurements (n = 6) of low (5 μg/L), medium (20 μg/L), and high (40 μg/L) concentrations of Sb(III) and Sb(V) were less than 4%. The results of spiking and recovery experiments for the extracting solutions of soil, sediments, and plants showed that the spiked recoveries of the two species ranged from 92% to 103%. This method has been used to determine the antimony species in extracts of environmental samples.
研究领域:
环境科学
·
分析化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ENVIRONMENTAL MANAGEMENT
·
2023
·
IF 8.7
Yi Lu,Zhaoxue Zhang,Yingyang Wang,Fangyuan Peng,Zhaoguang Yang,Haipu Li
Boehmeria nivea L. (ramie) is a promising phytoremediation plant for antimony (Sb)-contaminated soils. However, the uptake, tolerance, and detoxification mechanisms of ramie to Sb, which are the basis for finding efficient phytoremediation strategies, remain unclear. In the present study, ramie was exposed to 0, 1, 10, 50, 100, and 200 mg/L of antimonite (Sb(III)) or antimonate (Sb(V)) for 14 days in hydroponic culture . The Sb concentration , speciation, subcellular distribution, and antioxidant and ionomic responses in ramie were investigated. The results illustrated that ramie was more effective in the uptake of Sb(III) than Sb(V). Most of the Sb accumulated in ramie roots, with the highest level reaching 7883.58 mg/kg. Sb(V) was the predominant species in leaves, with 80.77–96.38% and 100% in the Sb(III) and Sb(V) treatments, respectively. Immobilization of Sb on the cell wall and leaf cytosol was the primary mechanism of accumulation. Superoxide dismutase (SOD), catalase (CAT), and peroxidase (POD) contributed significantly to root defense against Sb(III), while CAT and glutathione peroxidase (GPX) were the major antioxidants in leaves. CAT and POD played crucial roles in the defense against Sb(V). B, Ca, K, Mg, and Mn in Sb(V)-treated leaves and K and Cu in Sb(III)-treated leaves may be related to the biological processes of Sb toxicity mitigation. This study is the first to investigate the ionomic responses of plants toward Sb and could provide valuable information for the phytoremediation of Sb-polluted soils.
研究领域:
植物学
·
环境科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF ENVIRONMENTAL MANAGEMENT
·
2023
·
IF 8.7
Yi Lu,Fangyuan Peng,Yingyang Wang,Zhaoguang Yang,Haipu Li
Soil antimony (Sb) pollution is a global concern that threatens food security and human health. Boehmeria nivea L. (ramie) is a promising phytoremediation plant exhibiting high tolerance and enrichment capacity for Sb. To reveal the molecular mechanisms and thus enhance the ramie uptake, transport, and detoxification of Sb with practical strategies, a hydroponic experiment was conducted to compare the physiological and transcriptomic responses of ramie towards antimonite (Sb(Ⅲ)) and antimonate (Sb(Ⅴ)). Phenotypic results showed that Sb(Ⅲ) had a stronger inhibitory effect on the growth of ramie. Root Sb content under Sb(Ⅲ) was 2.43 times higher than that in Sb(Ⅴ) treatment. Based on the ribonucleic acid sequencing (RNA-Seq) technique, 3915 and 999 significant differentially expressed genes (DEGs) were identified under Sb(Ⅲ) and Sb(Ⅴ), respectively. Transcriptomic analysis revealed that ramie showed different adaptation strategies to Sb(Ⅲ) and Sb(V). Key DEGs and their involved pathways such as catalytic activity , carbohydrate metabolisms , phenylpropanoid biosynthesis, and cell wall modification were identified to perform crucial roles in Sb tolerance and detoxification. Two heavy metal-associated domain-type genes, six heavy metal-associated isoprenylated plant proteins, and nine ABC transporters showed possible roles in the transport and detoxification of Sb. The significant upregulation of NRAMP5 and three NIPs suggested their roles in the transport of Sb(V). This study is the basis for future research to identify the exact genes and biological processes that can effectively enhance Sb accumulation or improve plant tolerance to Sb, thereby promoting the phytoremediation of Sb-polluted soils.
研究领域:
环境科学
·
植物科学
·
分子生物学
·
植物修复
✓ 已验证
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）