Algal Research-Biomass Biofuels and Bioproducts
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2018
·
IF 3.745
Xiang Wang,Wei Wei,Nian-Jing Li,Wasiqi Yuan,Yu Ding,Wei-Dong Yang,Jie-Sheng Liu,Srinivasan Balamurugan,Hong-Ye Li
Microalgal metabolic engineering holds great promise for algal biofuels. However, identification of the key lipid metabolic target remains challenging due to its complex regulation. In this study, we advocated an alternative strategy that potentially rewired lipid metabolism by unprecedented mechanisms. PNPLA3 , a human protein associated with non-alcoholic fatty liver disease (NAFLD), was firstly tested in microalgae for enhancing lipid accumulation . HsPNPLA3 was synthesized with a site mutation (I148M) and expressed in a model diatom Phaeodactylum tricornutum . Heterogeneous HsPNPLA3-I148M was successfully integrated, transcribed and expressed. Lipidomic analyses revealed that HsPNPLA3-I148M significantly elevated TAG content by 1.55-fold in algae, while algal growth and photosynthetic rate were not impaired. Fatty acid profile showed that content of C16:0, C18:1 and C20:4 was increased by 1.43-, 4.18- and 4.3-fold, respectively, which implied that HsPNPLA3-I148M might regulate the fatty acid substrate preference. Overall, the findings demonstrated that human PNPLA3 played a potential role in elevating TAG accumulation by regulating lipogenic enzymes and provide unprecedented insights into its functional significance.
研究领域:
生物化学
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生物技术
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代谢工程
✓ 已验证
DOI
高影响因子
ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY
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2018
·
IF 3.974
Benben Du,Zhenyan Zhang,Wanyue Liu,Yizhi Ye,Tao Lu,Zhigao Zhou,Yan Li,Zhanyu Fu,Haifeng Qian
Azoxystrobin (AZ) is an effective broad-spectrum fungicide . Due to its extensive application, AZ is detectable in aquatic ecosystems and thus influences aquatic organisms. In this study, the acute toxicity (96 h) of AZ at concentrations of 1.0 mg/L and 5.0 mg/L on the diatom Phaeodactylum tricornutum were examined. At the tested concentrations, AZ significantly inhibited P. tricornutum growth and destroyed its cellular structure. Furthermore, the mechanisms of AZ-induced toxicity on P. tricornutum changed as the exposure time extended. Forty-eight hours after exposure, AZ inhibited P. tricornutum growth primarily via inducing oxidative stress , which increased the activity of two main antioxidant enzymes, superoxide dismutase and peroxidase, and inhibited energy metabolism. However, after 96 h of treatment, the decline in the photosynthetic capacity of P. tricornutum demonstrated that the photosystem was the main AZ target. The pigment content and expression levels of genes related to photosynthetic electron transfer reactions were also significantly decreased. The present study describes AZ toxicity in P. tricornutum and is very valuable for assessing the environmental risk of AZ.
研究领域:
环境科学
·
毒理学
·
水生生态学
✓ 已验证
DOI
PubMed
高影响因子
FUEL
·
2022
·
IF 8.035
Guang-Bin Ye,Zi-Hao Qin,Xiao-Yun Bin,Jin-Hua Mou,Carol Sze Ki Lin,Hong-Ye Li,Xiang Wang
Due to its high lipid accumulation capability, Phaeodactylum tricornutum has attracted considerable attention as a promising candidate for biofuel production. However, the derived lipid cannot satisfy the industrial biofuel manufacturing requirements given its poor fatty acid characteristics. Genetic engineering, as a prospective approach, has been employed to overcome this bottleneck. Relevant research indicates that the fabG gene plays a crucial role in fatty acid biosynthesis in bacteria, but its significance in microalgae remains unclear. In this study, FabG was successfully introduced, transcribed, and overexpressed in P. tricornutum . FabG overexpression significantly enhanced lipid (1.49-fold) and fatty acid (1.31-fold) biosynthesis without altering growth and photosynthesis, and this method thus exhibits great potential in high-quality biodiesel production. Moreover, increased saturation of fatty acids (e.g., C16:0) and improved antioxidative activities enhanced the tolerance of transgenic P. tricornutum to high temperature stress. To conclude, this study reports a feasible approach for high-quality algae-based biofuel production via the unprecedented roles of FabG retrieved from diatom.
研究领域:
生物技术
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微生物学
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生物化学
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环境科学
✓ 已验证
DOI
高影响因子
AQUATIC TOXICOLOGY
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2016
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IF 3.557
Cai Zhang,Jiangtao Wang,Liju Tan,Xiaohua Chen
To explore toxic mechanisms of nano-ZnO on marine microalgae, algal growth inhibition test was carried out, and total Zn in the cell and total dissolved Zn in f/2 medium were determined. It was found that nano-ZnO was more toxic than bulk-ZnO on marine microalgae Skeletonema costatum . No matter under nano-ZnO or bulk-ZnO treatment, accumulation of intracellular Zn had a good linear correlation with growth inhibition ratio (IR). The total Zn content in the cell of microalgae was the dominant toxic mechanism of ZnO. Intracellular total Zn could be an indispensable parameter to indicate the toxic effects of nano-ZnO. Higher intracellular total Zn under nano-ZnO treatment than bulk-ZnO resulted in more toxicity of nano-ZnO on microalgae. Compared with Zn 2+ released by nano-ZnO into medium, lipid peroxidation (MDA level) injury, aggregation of nano-ZnO and transmembrane process of nano-ZnO also contributed to toxicity of nano-ZnO on Skeletonema costatum . The accumulation of intracellular Zn provides a new insight into toxic mechanisms of nano-ZnO.
研究领域:
环境毒理学
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海洋生物学
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纳米技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ENVIRONMENTAL POLLUTION
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2020
·
IF 6.793
Xiang Wang,Si-Fen Liu,Zi-Hao Qin,Srinivasan Balamurugan,Hong-Ye Li,Carol Sze Ki Lin
Waste streams have emerged as potential feedstocks for biofuel production via microbial bioconversion . Metabolic engineering of the microalga Phaeodactylum tricornutum in its lipid biosynthetic pathways has been conducted with an aim to improve lipid production. However, there has been only limited achievement in satisfying biofuel demands by utilising extracellular organic carbons from low-cost waste streams. Herein, we present a successive staged cultivation mode, based on a previously engineered strain that co-overexpresses two key triacylglycerol biosynthesis genes. We first optimised microalgal biomass and lipid production by using food waste hydrolysate and crude glycerol as the cultivation media. Food waste hydrolysate (5% v / v ) is a low-cost organic carbon source for enhanced microalgal biomass production, and the resulting lipid concentration was 1.08-fold higher with food-waste hydrolysate than that of the defined medium. Additionally, the resultant lipid concentration after using crude glycerol (100 mM) was 1.24-fold higher than that using the defined medium. Two carbon feeding modes (hybrid and sequential) were also performed to investigate the potential of engineered P. tricornutum with preliminary mechanistic analyses. The biodiesel properties of lipids produced in the hybrid mode were evaluated for potential application prospects. Collectively, this study demonstrates a waste stream utilisation strategy for efficient and sustainable microalgal biofuel production.
研究领域:
生物技术
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生物能源
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环境工程
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微生物学
✓ 已验证
DOI
PubMed
高影响因子
Biotechnology for Biofuels
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2017
·Vol. 10
·期 1
·1-14
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IF 5.203
Balamurugan Srinivasan,Wang Xiang,Wang Hong-Lei,An Chun-Jing,Li Hui,Li Da-Wei,Yang Wei-Dong,Liu Jie-Sheng,Li Hong-Ye
Background Microalgae have emerged as a potential feedstock for biofuels and bioactive components. However, lack of microalgal strains with promising triacylglycerol (TAG) content and desirable fatty acid composition have hindered its commercial feasibility. Attempts on lipid overproduction by metabolic engineering remain largely challenging in microalgae. Results In this study, a microalgal 1-acyl-sn-glycerol-3-phosphate acyltransferase designated AGPAT1 was identified in the model diatom Phaeodactylum tricornutum . AGPAT1 contained four conserved acyltransferase motifs I–IV. Subcellular localization prediction and thereafter immuno-electron microscopy revealed the localization of AGPAT1 to plastid membranes. AGPAT1 overexpression significantly altered the primary metabolism, with increased total lipid content but decreased content of total carbohydrates and soluble proteins. Intriguingly, AGPAT1 overexpression coordinated the expression of other key genes such as DGAT2 and GPAT involved in TAG synthesis, and consequently increased TAG content by 1.81-fold with a significant increase in polyunsaturated fatty acids, particularly EPA and DHA. Moreover, besides increased lipid droplets in the cytosol, ultrastructural observation showed a number of TAG-rich plastoglobuli formed in plastids. Conclusion The results suggested that AGPAT1 overexpression could elevate TAG biosynthesis and, moreover, revealed the occurrence of plastidial TAG synthesis in the diatom. Overall, our data provide a new insight into microalgal lipid metabolism and candidate target for metabolic engineering.
研究领域:
植物学
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生物化学
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生物技术
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分子生物学
✓ 已验证
DOI
PubMed
高影响因子
BIORESOURCE TECHNOLOGY
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2019
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IF 6.669
Xiang Wang,Srinivasan Balamurugan,Si-Fen Liu,Man-Man Zhang,Wei-Dong Yang,Jie-Sheng Liu,Hong-Ye Li,Carol Sze Ki Lin
This study investigates the prospective of utilizing kitchen wastewater and food wastes, biofuels industry byproducts as alternative water and carbon sources. Kitchen wastewater did not impede cellular growth rate of the evolved Phaeodactylum strain E70, which indicates its potential as an alternative to freshwater resources. Among the organic wastes assessed, food waste hydrolysate significantly increased cell growth. Supplement of crude glycerol in cultivation medium enhances the total fatty acid content. Mixed food waste hydrolysate and crude glycerol remarkably increased both the cell density and total fatty acid content. Also, the supplement of butylated hydroxytoluene alleviated the oxidative stress induced by impurities in organic wastes and concomitantly increased microalgal total fatty acids and polyunsaturated fatty acids content. The experimental results reported in this study show that a waste-based biorefinery could lead to utilization of organic waste resources for the efficient production of value-added products.
研究领域:
海洋生物学
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生物技术
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环境科学
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生物化学工程
✓ 已验证
DOI
PubMed
高影响因子
JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY
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2017
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IF 3.154
Xiang Wang,Yu-Hong Liu,Wei Wei,Xia Zhou,Wasiqi Yuan,Srinivasan Balamurugan,Ting-Bin Hao,Wei-Dong Yang,Jie-Sheng Liu,Hong-Ye Li
Microalgal long-chain polyunsaturated fatty acids (LC-PUFAs) have emerged as promising alternatives to depleting fish oils. However, the overproduction of LC-PUFAs in microalgae has remained challenging. Here, we report a sequential metabolic engineering strategy that systematically overcomes the metabolic bottlenecks and overproduces LC-PUFAs. Malonyl CoA-acyl carrier protein transacylase, catalyzing the first committed step in type II fatty acid synthesis, and desaturase 5b, involved in fatty acid desaturation, were coordinately expressed in Phaeodactylum tricornutum. Engineered microalgae hyper-accumulated LC-PUFAs, with arachidonic acid (ARA) and docosahexaenoic acid (DHA) contents of up to 18.98 μg/mg and 9.15 μg/mg (dry weight), respectively. Importantly, eicosapentaenoic acid (EPA) was accumulated up to a highest record of 85.35 μg/mg by metabolic engineering. ARA and EPA were accumulated mainly in triacylglycerides, whereas DHA was found exclusively in phospholipids. Combinatorial expression of these critical enzymes led to the optimal increment of LC-PUFAs without unbalanced metabolic flux and demonstrated the practical feasibility of generating sustainable LC-PUFA production.
研究领域:
生物技术
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代谢工程
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微藻生物技术
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脂质代谢
✓ 已验证
DOI
PubMed
高影响因子
ACS Applied Nano Materials
·
2023
·
IF 5.9
Muhammad Ibrar,Tao Wang,Yanqing Luo,Yajun Ruan,Shiqinq Zhu,Yue Wu,Shuangfei Li,Ming Ying,Xuewei Yang
Multicomponent heteronanostructures offering catalytic and optical properties have applications across various fields. Photonic crystals (diatom frustules) coated with Au and copper chalcogenide domains represent a unique nanosystem that integrates multiple plasmon resonances from guided-mode resonance, conduction electrons, and valence holes in a single nanoscale system. In this work, we fabricate an enzyme-assisted photonic crystal-enhanced plasmonic nanosystem using a live diatom (Thalassiosira pseudonana) for surface-enhanced Raman scattering (SERS) quantification of sarcosine, an early stage prostate cancer (PCa) biomarker. The biosynthesized heteronanostructure was constructed by coating bimetallic nanoparticles (Au/CuX) on the diatom frustule via a two-stage cultivation process. A silaffin peptide-tagged sarcosine oxidase (SoX) was designed for specific substrate recognition and oriented conjunction. The components were coupled into a single entity (SoX-immobilized Au/CuX-coated frustule, BioNPS) to overcome the interenzyme distance and analyte trade-offs between mass transport. The sarcosine detection by BioNPS outperforms suspended bimetallic nanoparticles and single NP-coated diatom frustules. The improvement is attributed to the coupling of photonic frustule guided-mode resonance to the localized surface plasmonic resonance of bimetallic NPs via both electromagnetic and CT mechanisms. The cascade reaction in close proximity greatly enhances the catalytic efficiency by 5.47-fold compared to the solution-phase assay. The biochem nanosystem precisely detects tiny sarcosine concentration changes in the urine samples of PCa patients and healthy individuals. As a proof of concept, the in vivo fabrication of photonic/plasmonic heterostructures with tunable properties holds great promise for noninvasive biomarker screening.
研究领域:
纳米技术
·
生物医学工程
·
癌症研究
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材料科学
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分析化学
·
生物物理学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）