APPLIED MICROBIOLOGY AND BIOTECHNOLOGY
·
2022
·Vol. 106
·期 9
·3625-3637
·
IF 5.56
Wang Juan,Qu Ge,Xie Leipeng,Gao Chao,Jiang Yingying,Zhang Yi-Heng P. Job,Sun Zhoutong,You Chun
Abstract Dihydroxy-acid dehydratase (DHAD) plays an important role in the utilization of glycerol or glucose for the production of value-added chemicals in the in vitro synthetic enzymatic biosystem. The low activity of DHAD in the dehydration of glycerate to pyruvate hampers its applications in biosystems. Protein engineering of a thermophilic DHAD from Sulfolobus solfataricus (SsDHAD) was performed to increase its dehydration activity. A triple mutant (I161M/Y145S/G205K) with a 10-fold higher activity on glycerate dehydration was obtained after three rounds of iterative saturation mutagenesis (ISM) based on computational analysis. The shrunken substrate-binding pocket and newly formed hydrogen bonds were the reason for the activity improvement of the mutant. For the in vitro synthetic enzymatic biosystems of converting glucose or glycerol to L-lactate, the biosystems with the mutant SsDHAD showed 3.32- and 2.34-fold higher reaction rates than the wild type, respectively. This study demonstrates the potential of protein engineering to improve the efficiency of in vitro synthetic enzymatic biosystems by enhancing the enzyme activity of rate-limited enzymes. Key points • A screening method was established for the protein engineering of SsDHAD. • A R3 mutant of SsDHAD with 10-fold higher activity was obtained. • The R3 mutant exhibits higher productivity in the in vitro biosystems. Graphical abstract
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高影响因子
JOURNAL OF APPLIED PHYCOLOGY
·
2022
·Vol. 34
·期 3
·1709-1719
·
IF 3.404
Li Jing,Pang Shaojun,Su Li,Shan Tifeng
Phlorotannins are among the most important defensive molecules in kelp. They have been majorly identified in brown algae so far. Type III polyketide synthase (PKS) is regarded as one of the enzymes catalyzing a major step in the biosynthetic pathway of phlorotannins. In this study, a type III PKS gene ( sjPKS1 ) is characterized from the economic brown alga Saccharina japonica sporophyte. It contains 7 exons and 6 introns. The sjPKS1 open reading frame consists of 1245 nucleotides encoding a protein of 414 amino acids. The sjPKS1 are 87%, 83%, and 82% identical to that of Ectocarpus siliculosus , Sargassum binderi , and Sargassum fusiforme at the nucleotide level, respectively. While the amino acid sequences of sjPKS1 share more than 90% identity to that of the three brown algae species. The sjPKS1 expression at 200 µmol photons m −2 s −1 was significantly higher than at 20 and 50 µmol photons m −2 s −1 in sporophytic seedlings, so did the content of soluble phlorotannins inside the plants. Seven motifs in response to light are identified in the 5′ flanking region of sjPKS1 and two potential transcription factors are predicted by screening yeast one-hybrid library.
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APPLIED MICROBIOLOGY AND BIOTECHNOLOGY
·
2015
·Vol. 99
·期 17
·7035-7045
·
IF 3.337
Zhou Pengfei,Yang Jiazeng,Zhu Jianhua,He Shuijie,Zhang Wenjin,Yu Rongmin,Zi Jiachen,Song Liyan,Huang Xuesong
Long-term stable cell growth and production of vindoline, catharanthine, and ajmalicine of cambial meristematic cells (CMCs) from Catharanthus roseus were observed after 2 years of culture. C. roseus CMCs were treated with β-cyclodextrin (β-CD) and methyl jasmonate (MeJA) individually or in combination and were cultured both in conventional Erlenmeyer flasks (100, 250, and 500 mL) and in a 5-L stirred hybrid airlift bioreactor. CMCs of C. roseus cultured in the bioreactor showed higher yields of vindoline, catharanthine, and ajmalicine than those cultured in flasks. CMCs of C. roseus cultured in the bioreactor and treated with 10 mM β-CD and 150 μM MeJA gave the highest yields of vindoline (7.45 mg/L), catharanthine (1.76 mg/L), and ajmalicine (58.98 mg/L), concentrations that were 799, 654, and 426 % higher, respectively, than yields of CMCs cultured in 100-mL flasks without elicitors. Quantitative reverse transcription (RT)-PCR showed that β-CD and MeJA upregulated transcription levels of genes related to the biosynthesis of terpenoid indole alkaloids (TIAs). This is the first study to report that β-CD induced the generation of NO, which plays an important role in mediating the production of TIAs in C. roseus CMCs. These results suggest that β-CD and MeJA can enhance the production of TIAs in CMCs of C. roseus , and thus, CMCs of C. roseus have significant potential to be an industrial platform for production of bioactive alkaloids.
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Journal of Ocean University of China
·
2016
·Vol. 15
·期 3
·533-540
·
IF 0.509
Fu Zhifei,Li Haihua,Liu Hongbing,Hu Shuman,Li Yueying,Wang Mengxue,Guan Huashi
The response surface methodology (RSM) combined with bioassays was employed to optimize the extraction process of crude fucose-containing sulphated polysaccharides (cFCSP) from Sargassum fusiforme . The central composite design (CCD) was used with four variables, five levels, and four responses. The four variables were pH value of hydrochloric acid solution, extraction temperature (°C), ratio of liquid to raw material (mL g −1 ), and extraction time (h), respectively. Chemical and bioassay indices were used in combination as the response parameters, which included the yield of cFCSP, fucose content, proliferation rate of spleen cells, and lipopolysaccharide-induced proliferation of splenocytes. The experimental data were fitted to a second-order polynomial equation using multiple regression analysis, and examined using the appropriate statistical methods. The best extraction conditions were as follows: the pH value of hydrochloric acid solution was 3.50; the extraction temperature was 100°C; the ratio of liquid to raw material was 15.00 mL g −1 and the extraction time was 2.50 h. The experimental yield was close to the predicted from the model. The extract could promote spleen lymphocyte proliferation, especially the lipopolysaccharide-induced lymphocyte proliferation in vitro, which suggested that its immunomodulatory effect on B lymphocytes. Therefore, cFCSP extracted from S. fusiforme could be utilized as an immunostimulant in functional foods and pharmaceutical industry in future.
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JOURNAL OF NANOBIOTECHNOLOGY
·
2023
·Vol. 21
·期 1
·1-14
·
IF 10.2
Ren Yiming,Chen Yi,Chen Wei,Deng Haotian,Li Peiqi,Liu Yubo,Gao Cangjian,Tian Guangzhao,Ning Chao,Yuan Zhiguo,Sui Xiang,Liu Shuyun,Guo Quanyi
Successful biomaterial implantation requires appropriate immune responses. Macrophages are key mediators involved in this process. Currently, exploitation of the intrinsic properties of biomaterials to modulate macrophages and immune responses is appealing. In this study, we prepared hydrophilic nanofibers with an aligned topography by incorporating polyethylene glycol and polycaprolactone using axial electrospinning. We investigated the effect of the nanofibers on macrophage behavior and the underlying mechanisms. With the increase of hydrophilicity of aligned nanofibers, the inflammatory gene expression of macrophages adhering to them was downregulated, and M2 polarization was induced. We further presented clear evidence that the inflammasome NOD-like receptor thermal protein domain associated protein 3 (NLRP3) was the cellular sensor by which macrophages sense the biomaterials, and it acted as a regulator of the macrophage-mediated response to foreign bodies and implant integration. In vivo, we showed that the fibers shaped the implant-related immune microenvironment and ameliorated peritendinous adhesions. In conclusion, our study demonstrated that hydrophilic aligned nanofibers exhibited better biocompatibility and immunological properties.
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JOURNAL OF NANOBIOTECHNOLOGY
·
2023
·Vol. 21
·期 1
·1-24
·
IF 10.2
Liu Ziyao,Chen Bei,Xiang Shijun,Hu Shuo
Background Pharmacotherapy constitutes the first-line treatment for depression. However, its clinical use is hindered by several limitations, such as time lag, side effects, and narrow therapeutic windows. Nanotechnology can be employed to shorten the onset time by ensuring permeation across the blood brain barrier (BBB) to precisely deliver more therapeutic agents; unfortunately, formidable challenges owing to the intrinsic shortcomings of commercial drugs remain.Results Based on the extraordinary capability of monoamines to regulate the neuronal environment, we engineer a network nanocapsule for delivering serotonin (5-hydroxytryptamine, 5-HT) and catalase (CAT) to the brain parenchyma for synergistic antidepression therapy. The nanoantidepressants are fabricated by the formation of 5-HT polymerization and simultaneous payload CAT, following by surface modifications using human serum albumin and rabies virus glycoprotein. The virus-inspired nanocapsules benefit from the surface-modifying strategies and exhibit pronounced BBB penetration. Once nanocapsules reach the brain parenchyma, the mildly acidic conditions trigger the release of 5-HT from the sacrificial nanocapsule. Releasing 5-HT further positively regulate moods, relieving depressive symptoms. Meanwhile, cargo CAT alleviates neuroinflammation and enhances therapeutic efficacy of 5-HT.Conclusion Altogether, the results offer detailed information encouraging the rational designing of nanoantidepressants and highlighting the potential of nanotechnology in mental health disorder therapies.Graphical abstract
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Nanoscale Research Letters
·
2014
·Vol. 9
·期 1
·1-8
·
IF 2.481
Liu Zhong-Tao,Xiong Li,Liu Zhi-Peng,Miao Xiong-Ying,Lin Liang-Wu,Wen Yu
This study aimed to compare the inhibitory effects of photosensitizers loaded in hollow silica nanoparticles and conventional photosensitizers on HepG2 human hepatoma cell proliferation and determine the underlying mechanisms. Photosensitizers (conventional Photosan-II or nanoscale Photosan-II) were administered to in vitro cultured HepG2 hepatoma cells and treated by photodynamic therapy (PDT) with various levels of light exposure. To assess photosensitizers' effects, cell viability was determined by 3-(4, 5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. In addition, apoptotic and necrotic cells were measured by flow cytometry and the expression of caspase-3 and caspase-9 evaluated by western blot. Finally, the in vivo effects of nanoscale and conventional photosensitizers on liver cancer were assessed in nude mice. Nanoscale Photosan-II significantly inhibited hepatoma cell viability in a concentration-dependent manner and this effect was more pronounced with high laser doses. Moreover, nanoscale photosensitizers performed better than the conventional ones under the same experimental conditions (p < 0.05). Flow cytometry data demonstrated that laser-induced cell death was markedly increased after treatment with nanoscale Photosan-II in comparison with free Photosan-II (p < 0.05). Activated caspase-3 and caspase-9 levels were significantly higher in cells treated with Photosan-II loaded in silica nanoparticles than free Photosan-II (p < 0.05). Accordingly, treatment with nanoscale photosensitizers resulted in improved outcomes (tumor volume) in a mouse model of liver cancer, in comparison with conventional photosensitizers. Hollow silica nanoparticles containing photosensitizer more efficiently inhibited hepatoma cells than photosensitizer alone, through induction of apoptosis, both in vivo and in vitro.
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Cell Death Discovery
·
2023
·Vol. 9
·期 1
·1-11
·
IF 7
Zhang Libo,Ren Zhen,Lü Jinhui,Mo Xinhai,Lin Jie,Li Ya,Ma Wenjing,Liu Pengfei,Shen Yajing,Zhao Qian,Qian Lu,Cheng Xiaoxin,Yu Zuoren,Zhang Bo
Nanomaterials have been well demonstrated to have the potential to be used for tumor cell-targeted drug delivery. Targeted inhibition of miR-221 was proved to promote the sensitivity of triple genitive breast cancer (TNBC) cells to chemo-drugs. In order to improve the chemotherapeutic effect in TNBC, herein, we developed a novel kind of nanoparticles shelled with PLGA and loaded with perfluoropentane (PFP), paclitaxel (PTX), and anti-miR-221 inhibitor, which was named PANP. Ultrasound-triggered vaporization of PFP in PANPs was utilized for real-time imaging track of the nanoparticles in vivo. In addition, macrophages were applied for the internalization of PANPs to form RAW-PANP with strong chemotaxis to accumulate around cancer cells. Nanoparticles with different contents did not cause M2 polarization compared with the control group but caused polarization toward M1. We compared the inherent tumor-homing behavior of macrophages containing different contents with that of normal macrophages and no significant abnormalities were observed. After injection into the tumor-burden mice, RAW-PANPs showed enrichment within tumor tissues. Upon the ultrasound cavitation-triggered burst, PTX was released in the tumor. Meanwhile, the release of anti-miR-221 improved the sensitivity of tumor cells to PTX. As a result, RAW-PANPs showed high efficiency in suppressing TNBC cell proliferation in vitro and inhibiting tumor growth and progression in vivo. The treatments did not induce liver, heart, or kidney injury. In conclusion, the current study not only developed a macrophage-carried, ultrasound-triggered, cancer cell-targeted chemotherapeutic system, but also demonstrated a miRNA-based technique to promote drug sensitivity of cancer cells, which holds strong potential to treat patients with TNBC, especially for those suffering drug-resistance. The innovation of this study is to use macrophages to deliver nanoparticles to the tumors and then use ultrasound locally to burst the nanoparticles to release the miRNA and PTX.
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JOURNAL OF NANOPARTICLE RESEARCH
·
2015
·Vol. 17
·期 3
·1-17
·
IF 2.184
Hou Lin,Feng Qianhua,Wang Yating,Zhang Huijuan,Jiang Guixiang,Yang Xiaomin,Ren Junxiao,Zhu Xiali,Shi Yuyang,Zhang Zhenzhong
Graphene oxide (GO) with strong optical absorption in the near-infrared (NIR) region has shown great potential both in photothermal therapy and drug delivery. In this work, hyaluronic acid (HA)-functionalized GO (HA-GO) was successfully synthesized and controlled loading of mitoxantrone (MIT) onto HA-GO via π – π stacking interaction was investigated. The results revealed that drug-loaded nanosheets with high loading efficiency of 45 wt% exhibited pH-sensitive responses to tumor environment. Owing to the receptor-mediated endocytosis, cellular uptake analysis of HA-GO showed enhanced internalization. In vivo optical imaging test demonstrated that HA-GO nanosheets could enhance the targeting ability and residence time in tumor site. Moreover, the anti-tumor activity of free MIT, MIT/GO, and MIT/HA-GO in combination with NIR laser was investigated using human MCF-7 cells. In vitro cytotoxicity study revealed that HA-GO could stand as a biocompatible nanocarrier and MIT/HA-GO demonstrated remarkably higher toxicity than free MIT and MIT/GO, with IC 50 of 0.79 µg ml −1 . Tumor cell-killing potency was enhanced when MIT/HA-GO were combined with NIR irradiation, and the IC 50 of MIT/HA-GO plus laser irradiation was 0.38 µg ml −1 . In vivo, MIT/HA-GO plus NIR laser irradiation with the tumor growth inhibition of 93.52 % displayed greater anti-tumor effect compared with free MIT and MIT/GO with or without laser irradiation. Therefore, the MIT/HA-GO nanosheets may potentially be useful for further development of synergistic cancer therapy.
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Food Analytical Methods
·
2019
·Vol. 12
·期 12
·2777-2784
·
IF 2.413
Li Hong,Zhao Chunxi,Tian Hao,Yang Yaling,Li Wanyi
An uncomplicated, valid, and convenient way for detection of lycopene and β-carotene in fruit juice samples using acid–base-induced deep eutectic solvent (DES) liquid-liquid microextraction (DES-ABLLME) prior to HPLC was developed. The ternary fatty acid DESs were prepared by C 9 :C 10 :C 11 (2:1:1), which serve as hydrogen bond donors and hydrogen bond acceptors synchronously. In extraction procedure, NH 3 ·H 2 O was used as the emulsifier and reacted with DESs with a milk solution, which can significantly increase the extraction efficiency. HCl was used as the de-emulsifier, which could break the state of emulsification. At optimum conditions, the calibration graphs were linear in the concentration range from 0.1 to 100 μg mL −1 for lycopene and from 0.025 to 5.00 μg mL −1 for β-carotene. The limits of detection (LODs) were 0.05 and 0.002 μg mL −1 for lycopene and β-carotene, respectively. The RSD values were varied from 1.3 to 4.1%. Finally, the proposed method was applied to analyze β-carotene and lycopene in fruit juices.
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Frontiers of Environmental Science & Engineering
·
2023
·Vol. 17
·期 11
·1-12
·
IF 6.4
Chen Meiling,Yin Mengjie,Su Yuetan,Li Ruizhe,Liu Kezhou,Wu Zhongbiao,Weng Xiaole
Despite the large emission of chlorinated volatile organic compounds (CVOCs) into the atmosphere, the ultimate fate of these compounds remains largely unknown. Herein, we explore the photochemical conversion of an important class of CVOCs, namely chlorobenzene (CB), on mineral α-Fe 2 O 3 particulates under atmospheric relevant conditions. A series of chamber reactions composed of the CB with/without SO 2 or NO 2 are performed, followed by in situ diffuse reflectance infrared Fourier transform spectroscopy measurements and density functional theory calculations. We show that CB can be considerably degraded by α-Fe 2 O 3 under light irradiation, whereas the reaction is markedly suppressed by adding SO 2 or NO 2 owing to their competitive adsorption and surface acidification. In particular, we discover that CB can be ultimately converted into polychlorinated dibenzo- p -dioxins and dibenzofurans (PCDD/Fs) under dark state or light irradiation, suggesting a possible origin of atmospheric PCDD/Fs from this overlooked photochemical source.
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JOURNAL OF POLYMER RESEARCH
·
2021
·Vol. 28
·期 7
·1-10
·
IF 3.097
Xian Wenqi,Yuan Jie,Xie Zhengbin,Ou Wei,Liu Xiaoxuan,Liu Baohua
A series of CO 2 copolymer-based waterborne polyurethanes with high solid content were successfully prepared by using CO 2 copolymer diol, isophorone diisocyanate, and dimethylol propionic acid as the donors of hydrophilic groups. In order to obtain of the emulsion with high solid content and good physical property, the synthesis conditions of CO 2 copolymer-based waterborne polyurethane were studied. The influence of dimethylol propionic acid content and synthesis process on the physical property of the emulsion was also investigated. Results show that CO 2 copolymer-based waterborne polyurethane with high solid content can be synthesized by chain expansion at relatively low temperature. The waterborne polyurethane emulsion particle size distribution was wide. As the content of hydrophilic groups in prepolymer increased, the viscosity and water absorption increased obviously, this is difficult to synthesize waterborne polyurethane with high solid content and low water absorption. Thermal gravimetric analysis shows that the higher the chain extending temperature of CO 2 copolymer-based waterborne polyurethane, the higher the thermal decomposition temperature. When the CO 2 molar content of CO 2 copolymer diol is about 30%, the CO 2 copolymer-based waterborne polyurethane has high strength and better water resistance.
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危险品化学品经营许可证（带存储）