APPLIED BIOCHEMISTRY AND BIOTECHNOLOGY
·
2022
·Vol. 194
·期 11
·5274-5291
·
IF 3.094
Lei Jiping,Tang Kexin,Zhang Ting,Li Yan,Gao Zhen,Jia Honghua
2-O-α-D-Glucosyl glycerol (2-αGG) can be used as a multipurpose anti-aging, cell-stimulating, and skin moisturizing agent in the cosmetic industry. Sucrose phosphorylase (SPase) has been widely used in the production of 2-αGG. In this paper, the gene encoding sucrose phosphorylase from Bifidobacterium longum (BlSP) was inserted into pRSF-Duet-1 to construct the recombinant plasmid pRSF-BlSP and was functionally expressed in E. coli BL21(DE3) to be used as a biocatalyst for the synthesis of 2-αGG firstly. The mutations of BlSP were carried out based on alanine scanning, and a positive mutant G293A with a 50% increase in activity for 2-αGG production was identified. Mutant G293A has less K m and bigger k cat / K m towards glycerol than the parental BlSP. Subsequently, the production of 177.6 g/L 2-αGG was attained from 1 M sucrose and 1.2 M glycerol catalyzed by 17 mg/mL G293A mutant. This study indicated that BlSP has good potential in the production of 2-αGG.
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3 Biotech
·
2021
·Vol. 11
·期 7
·1-9
·
IF 2.406
Chang Siyuan,Pan Xin,Zhao Mingzhe,Li Guoqing,Wang Xue,Fan Yachen,Song Wei,Li Bingfeng,Zhang Sen,He Xuejun
Glycosylation is a prominent biological mechanism, affecting the structural and functional diversity of many natural products. In this study, a novel thermostable uridine diphosphate-dependent glycosyltransferase gene PpGT1 was cloned from Paenibacillus polymyxa NJPI29 and recombinantly expressed in B. subtilis WB600. The purified PpGT1 had a molecular weight of 45 kDa, as estimated using SDS-PAGE. The PpGT1 could catalyze the glycosylation of vanillic acid, methyl vanillate, caffeic acid, cinnamic alcohol, and ferulic acid. Moreover, PpGT1 possessed good thermostability and retained 80% of its original activity even after 12 h of incubation at 45 °C. In addition, PpGT1 remained stable within a neutral to alkaline pH range as well as in the presence of metal ions. The synthesis of methyl vanillate 4- O -β-D-glucoside by purified PpGT1 reached a yield 3.58 mM in a system with pH 8.0, 45 °C, 12 mM UDP-Glc, and 4 mM methyl vanillate. 3D-structure-based amino acid sequence alignments revealed that the catalytic residues and C-terminated PSPG motif were conserved. These unusual properties indicated that PpGT1 is a candidate UGT for valuable natural product industrial applications.
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PLANTA
·
2021
·Vol. 253
·期 5
·1-8
·
IF 4.116
Fu Jinqiu,Xu Wenbo,Huang Wei,Wang Bipeng,Li Shengchun,Zhang Jiang,Chang Ling
Main conclusion Importation of taxadiene synthase into chloroplasts is important for the efficient heterologous production of taxadiene. Abstract Taxadiene, the first committed precursor to taxol, is synthesized from geranylgeranyl pyrophosphate (GGPP) by action of taxadiene synthase (TS). Heterologous production of taxadiene could potentially rely on both cytosolic mevalonic acid (MVA) pathway and the plastidic methylerythritol phosphate (MEP) pathway. We suggest the compartmentalized engineering in chloroplast as an efficient approach for taxadiene production. In this study, we directly introduced the TS gene from Taxus brevifolia into the tobacco chloroplast genome and found that the transplastomic plants accumulated a low content of taxadiene, ~ 5.6 μg/g dry weight (DW). Moreover, we tried a combination of MEP and MVA pathways for taxadiene synthesis by nuclear transformation with a truncated version of TS (without encoding a transit peptide) into the transplastomic plants. However, this did not further improve the taxadiene production. In contrast, we found that taxadiene could be produced up to 87.8 μg/g DW in leaves of transgenic plants expressing TS with a chloroplast transit peptide, which was significantly higher than that in leaves of transplastomic plants. Thus, this study highlights the importance of TS importation into chloroplast for production of taxadiene.
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Frontiers of Chemical Science and Engineering
·
2019
·Vol. 14
·期 4
·546-560
·
IF 2.809
Wang Hanlu,Jibrin Idris,Zeng Xingye
Catalysts for the desulfurization of gasoline samples were synthesized via the immobilization of well-dispersed phosphotungstic acid (HPW) on Mobil composition of matter-twenty-two (MWW) zeolite. Characterization results indicated that these catalysts possess a mesoporous structure with the retention of the Keggin structure of immobilized HPW. Relevant reaction parameters influencing sulfur removal were systematically investigated, including HPW loading, catalyst dosage, temperature, initial S-concentration, molar ratio of oxidant to sulfide (O/S), volume ratio of MeCN to model oil (Ext./oil), and sulfide species. The 40 wt-% HPW/MWW catalyst exhibited the highest catalytic activity with 99.6% dibenzothiophene sulfur removal from prepared samples. The 40 wt-% HPW/MWW catalyst was recycled four times and could be easily regenerated. Finally, as an exploratory study, straight-run-gasoline and fluid catalytic cracking gasoline were employed to accurately evaluate the desulfurization performance of 40 wt-% HPW/MWW. Our research provides new insights into the development and application of catalysts for desulfurization of gasoline.
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Bioresources and Bioprocessing
·
2022
·Vol. 9
·期 1
·1-9
·
IF 4.983
Ma Yue,Li Tianzhen,Tan Zijian,Ma Long,Liu Haifeng,Zhu Leilei
Catalytic valorization of raw glycerol derived from biodiesel into high-value chemicals has attracted great attention. Here, we report chemoenzymatic cascade reactions that convert glycerol to lactic acid and glycolic acid. In the enzymatic step, a coenzyme recycling system was developed to convert glycerol into 1,3-dihydroxyacetone (DHA) with a yield of 92.3% in potassium phosphate buffer (300 mM, pH 7.1) containing 100 mM glycerol, 2 mM NAD + , 242 U/mL glycerol dehydrogenase-GldA and NADH oxidase-SpNox K184R at 30 °C. Subsequently, NaOH or NaClO 2 catalyzes the formation of lactic acid and glycolic acid from DHA. The high yield of lactic acid (72.3%) and glycolic acid (78.2%) verify the benefit of the chemoenzymatic approaches. Graphical Abstract
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Bioresources and Bioprocessing
·
2022
·Vol. 9
·期 1
·1-11
·
IF 4.983
Liu Yangyang,Sun Qihao,Hao Mengyang,Tan Wen‑Song,Cai Haibo
The application of natural killer (NK) cells as potential antitumor effector cells appears to be valuable for immunotherapies. However, the clinical use of NK cells is limited because the technical difficulties associated with mass production NK cells at sufficiently high numbers represents a great challenge. Ex vivo expansion of NK cells is a key technology for cell therapy. Bioreactor systems can generate homogeneous culture condition and modulate the environmental and biochemical cues. In this study, a novel magnetically controlled bioreactor was developed for supporting NK cells ex vivo expansion. Using synthetic magnetic beads, the stirring device of the magnetically controlled bioreactor generated reduced shearing force. The intermittent magnetic field was applied for magnetic beads movement to homogenize the culture system. NK-92 cells were cultured in the magnetically controlled bioreactor and the expansion and function of expanded cells were investigated on day 8. The results showed that the expansion of NK-92 cells in the bioreactor was 67.71 ± 10.60-fold, which was significantly higher than that of the T25 culture flask (P < 0.05). Moreover, the proportions of CD3−CD56+ cells and cell killing activity of expanded cells in the bioreactor did not reveal any differences compared to T25 flasks. Taken together, this study demonstrated the possibility of magnetically controlled bioreactor as a potent strategy in NK cells production for facilitating cancer immunotherapy.
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Metabolomics
·
2022
·Vol. 18
·期 11
·1-14
·
IF 4.747
Li Yongyu,Tian Sicheng,Yang Le,Bao Xiaoming,Su Lin,Zhang Xiang,Liu Sijing,Zhu Yalan,Yang Jiaxue,Lin Hua,Zhang Jing,Zeng Jumei,Wang Chuan,Tang Tian
Introduction Previous reports revealed the role played by Salmonella PhoP–PhoQ system in virulence activation, antimicrobial tolerance and intracellular survival, the impact of PhoP–PhoQ on cell metabolism has been less extensively described. Objectives The aim of this study is to address whether and how the PhoP–PhoQ system affects the cell metabolism of Salmonella. Methods We constructed a Salmonella phoP deletion mutant strain TT-81 (PhoP-OFF), a Salmonella PhoP constitutively expressed strain TT-82 (PhoP-ON) and a wild-type Salmonella PhoP strain TT-80 (PhoP-N), using P22-mediated generalized transduction or λ Red-mediated targeted mutagenesis. We then measured the in vitro growth kinetics of all test strains and determined their metabolomic and transcriptomic profiles using gas chromatography coupled with tandem mass spectrometry (GC–MS/MS) and RNA-seq technique, respectively. Results Low-Mg 2+ conditions impaired the growth of the phoP deletion mutant strain TT-81 (PhoP-OFF) dramatically. 42 metabolites in the wild-type PhoP strain TT-80 (PhoP-N) and 28 metabolites in the PhoP constitutively expressed strain TT-82 (PhoP-ON) changed by the absence of phoP . In contrast, the level of 19 compounds in TT-80 (PhoP-N) changed comparing to the PhoP constitutively expressed strain TT-82 (PhoP-N). The mRNA level of 95 genes in TT-80 (PhoP-N) changed when phoP was disrupted, wherein 78 genes downregulated and 17 genes upregulated. 106 genes were determined to be differentially expressed between TT-81 (PhoP-OFF) and TT-82 (PhoP-ON). While only 16 genes were found to differentially expressed between TT-82 (PhoP-ON) and TT-80 (PhoP-N). Conclusion Our findings confirmed the impact of PhoP–PhoQ system on lipopolysaccharide (LPS) modification, energy metabolism, and the biosynthesis or transport of amino acids. Most importantly, we demonstrated that the turnover of a given metabolite could respond differentially to the level of phoP . Taken together, the present study provided new insights into the adaptation of Salmonella to the host environment and helped to characterize the impact of the PhoP–PhoQ system on the cell metabolism.
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JOURNAL OF NANOBIOTECHNOLOGY
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2022
·Vol. 20
·期 1
·1-13
·
IF 9.429
Gu Jun,Zhao Gang,Yu Jiangkun,Xu Pei,Yan Jiabin,Jin Zhengshuai,Chen Sheng,Wang Yong,Zhang Leshuai W.,Wang Yangyun
Although combination chemoimmunotherapy shows promising clinical results for cancer treatment, this approach is largely restricted by variable objective response rate and severe systemic adverse effects of immunotherapeutic antibody and chemotherapeutic drugs. Therefore, an in situ-formed therapeutic silk-chitosan composite scaffold is fabricated in this study to allow local release of the chemotherapeutic drug doxorubicin (DOX) and JQ1 (small molecular inhibitor used for the extraterminal protein BRD4 and bromodomain) with control release kinetics. DOX-JQ1@Gel contains a pH-degradable group that releases therapeutics in a weak acidic tumor microenvironment. The released DOX could directly kill tumor cells or lead to immunogenic cell death, thereby triggering the response of antitumor immunity. Meanwhile, chemotherapy-triggered antigen release and JQ1-mediated PD-L1 checkpoint blockade cumulatively contribute to trigger the response of antitumor immunity. Finally, the DOX-JQ1@Gel is locally injected to evaluate its synergistic cancer therapeutic effect, which is expected to improve objective response rate of immunotherapy and minimize systemic side effects.Graphical Abstract
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NPG Asia Materials
·
2020
·Vol. 12
·期 1
·1-16
·
IF 8.131
Qian Chunyu,Xin Tianwen,Xiao Wanshu,Zhu Huajun,Zhang Qiang,Liu Lili,Cheng Ruoyu,Wang Zhen,Cui Wenguo,Ge Zili
Electrospun fiber membranes have been extensively researched for tissue repair; however, fiber angiogenesis has been a difficult problem because the biomaterials used to prepare the fiber cannot promote angiogenesis by themselves. To endow the fiber with the function of promoting angiogenesis and oral mucosa regeneration, surface-aminated liposomes (NH 2 -LIPs) encapsulating leptin, as well as silk fiber (SF) membranes that have been immersed overnight in polydopamine (PDA) solution were synthesized. The NH 2 -LIPs were then grafted onto the surfaces of SF through reactions between the catechol groups of PDA and the amino groups of NH 2 -LIPs to induce angiogenesis on the fiber surface and thus promote oral mucosa regeneration. The PDA-modified and NH 2 -LIP-modified SF retained the original fibrous morphology but increased the SF tensile strength from 1.95 MPa to 2.87 MPa. PDA changed the hydrophilicity of the fibers and improved the adhesion of fibroblasts on the fibrous membranes. Leptin loaded onto SF via PDA had no significant effect on cell proliferation and formed 162.7-node tubes in human umbilical vein endothelial cells (HUVECs) within 10 h, which demonstrated that leptin loaded onto SF can promote angiogenesis. Wound closure of mucosa covered in leptin-loaded fibrous membranes reached 99% at 14 days postsurgery. Histologic analysis showed that leptin-loaded SFs exhibited clear stratification of new mucosa, as well as a strong CD34 signal that indicated the presence of new blood vessels and confirmed the successful loading of leptin on the fiber. Therefore, this work successfully showed that NH 2 -LIPs grafted onto the surface of SFs via PDA endow the fibers with angiogenic abilities and promote oral mucosa regeneration.
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npj Flexible Electronics
·
2022
·Vol. 6
·期 1
·1-9
·
IF 12.019
Huang Yuan,Liu Binbin,Zhang Wenyue,Qu Gangrui,Jin Shunyu,Li Xianbo,Nie Zanxiang,Zhou Hang
A conductive, elastic, and biocompatible hybrid network hydrogel was prepared by cross-linking of locust bean gum, polyvinyl alcohol, and carbon nanotubes, yielding a rough top surface and smooth bottom surface. The merging of the two pieces of hydrogel flat face to flat face forms a highly elastic hydrogel with double-rough surfaces. A piezoresistive sensor assembled with the double-rough surface hydrogel sandwiched between two carbon cloth electrodes exhibits a high sensitivity (20.5 kPa-1, 0-1kPa), a broad detection range (0.1–100 kPa) and a reliable response for 1000 cycles. The rough contact area between the hydrogels and the carbon cloth is found critical in achieving ultra-high sensitivities in the low-pressure range. Moreover, further monolithic integration of the sensor with a flexible solid-state zinc ion battery ensures the self-powering of the sensor for various human motions detection applications.
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BMC GENOMICS
·
2019
·Vol. 20
·期 1
·1-19
·
IF 3.501
Lu Wei-Jia,Gao Fan-Xiang,Wang Yang,Zhang Qi-Ya,Li Zhi,Zhang Xiao-Juan,Zhou Li,Gui Jian-Fang
Background Accompanied with rapid growth and high density aquaculture, gibel carp has been seriously threatened by Carassius auratus herpesvirus ( Ca HV) since 2012. In previous study, distinct Ca HV resistances and immune responses were revealed in the diseased individuals of three gibel carp gynogenetic clones (A + , F and H). However, little is known about the gene expression changes in the survivors after Ca HV challenge, particularly their differences of innate and adaptive immune system between susceptible clone and resistant clone. Results We firstly confirmed the Ca HV carrier state in the survivors of three gibel carp clones after Ca HV challenge by evaluating the abundances of five Ca HV genes. The assay of viral loads indicated the resistant clone H possessed not only stronger resistance but also higher tolerance to Ca HV. Then, 2818, 4047 and 3323 differentially expressed unigenes (DEUs) were screened from the head-kidney transcriptome profiles of survivors compared with controls from clone A + , F and H. GO and KEGG analysis suggested that a persistent immune response might sustain in resistant clone H and F, while susceptible clone A + had a long-term impact on the circulatory system which was consistent with the major symptoms of bleeding caused by Ca HV. Among the top 30 enriched pathways of specifically up-regulated DEUs in respective clones, 26, 7 and 15 pathways in clone H, F and A + were associated with infections, diseases, or immune-related pathways respectively. In addition, 20 pathways in clone F belonged to “metabolism” or “biogenesis”, and 7 pathways involved in “circulatory system” were enriched in clone A + . Significantly, we revealed the differential expression changes of IFN system genes and immunoglobulin (Ig) genes among the survivors of three clones. Finally, myosins and Igs were identified as co-expression modules which were positively or negatively correlated to Ca HV viral loads respectively. Conclusions Our results revealed the common and distinct gene expression changes in immune and circulatory system in the survivors of three gibel carp gynogenetic clones with different Ca HV resistances. The current study represents a paradigm of differential innate and adaptive immune reactions in teleost, and will be beneficial to the disease-resistance breeding of gibel carp.
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Nano Research
·
2018
·Vol. 11
·期 8
·4278-4292
·
IF 7.994
Zhang Yapei,Li Yingying,Ma Jinlong,Wang Xinyu,Yuan Zhi,Wang Wei
A major impediment in the development of chitosan nanoparticles (CTS NPs) as effective drug delivery vesicles is their rapid clearance from blood and endosome entrapment. To overcome these problems, a convenient and promising template system was developed by decorating poly(methacrylic acid) (PMAA) to the surface of 10-hydroxy camptothecin (HCPT)-loaded CTS NPs (HCPT-CTS/PMAA NPs). The results show that the presence of negatively charged PMAA significantly elongated the blood circulation time of HCPT-CTS NPs from 12 to 24 h, and reduced the blood clearance (Cl) from 30.57 to 6.72 mL/h in vivo . The calculated area under curve (AUC 0-24h ) and terminal elimination half-life ( t 1/2 ) of HCPT-CTS/PMAA NPs were 4.37-fold and 2.48-fold compared with those of HCPT-CTS NPs. Furthermore, the positively charged HCPT-CTS/PMAA NPs triggered by tumor acidic microenvironment (pH 6.5) result in a 453-fold higher cellular uptake than the negatively charged counterparts at pH 7.4. Additionally, HCPT-CTS/PMAA NPs have the ability to escape endosomal entrapment via “proton sponge effect” after incubation with HepG2 cells for 3 h at pH 6.5. Taken together, these findings open up a convenient, low-cost, but effective way to prepare HCPT-CTS/PMAA NPs as a candidate for developing vectors with enhanced long blood circulation and endosomal escape ability in future clinical experiments.
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