Energies
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2022
·Vol. 15
·期 12
·4242
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IF 3.252
Xue-Yong Li,Jia-Ying Huang,Qiang Zhou,Yuan-Yuan Xu,Ponnandy Prabhu,Ye-Wang Zhang
Acetoin, a four-carbon hydroxyl-keto compound, is used in the food, pharmaceutical, and chemical industries. The cascade enzymatic production is considered a promising and efficient method to produce acetoin. However, the stability and compatibility of the enzymes under the same catalytic conditions are challenges that need to be resolved. In this work, alcohol dehydrogenase, acetaldehyde lyase, and NADH oxidase were selected to work at the same conditions to efficiently convert ethanol into acetoin. These three enzymes were immobilized on epoxy-modified magnetic nanomaterials to obtain highly stable biocatalysts. The stability and the immobilization conditions, including temperature, pH, enzyme–carrier ratio, and immobilization time, were optimized to obtain the immobilized enzymes with a high catalytic activity. The cascade reactions catalyzed by the immobilized enzymes yielded a high conversion of 90%, suggesting that the use of immobilized enzymes is a promising way to produce acetoin.Keywords:immobilization;NADH oxidase;acetaldehyde lyase;alcohol dehydrogenase;acetoin;cascade enzymatic reactions
研究领域:
生物技术
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酶学
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化学工程
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产品关联
DOI
高影响因子
Frontiers in Bioengineering and Biotechnology
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2021
·
IF 5.89
Zhou Li-Jian,Guo Li-Bin,Wei Wei,Lv Zhi-Xiang,Zhang Ye-Wang
Chondroitin AC lyase (ChSaseAC) is one of the essential polysaccharides lyases in low molecular chondroitin sulfate production. In this work, a novel PrChSaseAC from Pedobacter rhizosphaerae was successfully cloned, expressed in Escherichia coli. After optimizing the induction, the recombinant PrChSaseAC could be expressed efficiently at 0.1 mM IPTG, 25°C, and 12 h induction. Then, it was purified with Ni-NTA affinity chromatography. The characterization of the purified PrChSaseAC showed that it had high specific activity and good storage stability, which would favor the production of low molecular weight chondroitin sulfate. It also displayed activity toward chondroitin sulfate C and hyaluronic acid. PrChSaseAC had the highest activity at pH 7.5, 37°C, 10 mM Ca2+, and 5 mg/ml of chondroitin sulfate A. Molecular docking of substrate and enzyme showed the interactions between the enzyme and substrate; it revealed that the enzyme showed high activity to CS-A and hyaluronic acid, but lower activity to CS-C attributed to the structure of the binding pocket. The high stability and specific activity of the enzyme will benefit the industrial production or clinical treatment.
研究领域:
生物化学
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酶学
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生物技术
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药理学
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产品关联
DOI
PubMed
高影响因子
Biomass Conversion and Biorefinery
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2022
·Vol. 13
·期 17
·15837-15844
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IF 4.05
Di Junhua,Qin Lizhen,He Yu-Cai
A new type of metal-free solid acid catalyst ChCl:OA-SG(SiO 2 ) was firstly synthesized by loading deep eutectic solvent ChCl:oxalic acid on silica with sol–gel process using tetraethyl orthosilicate as silicon source. The properties of the catalyst were characterized by Fourier transform infrared spectrum, X-ray diffraction, scanning electron microscope, and Brunauer-Emmet-Teller. Highest furfural (FF) yield reached 41.2% from corncob with ChCl:OA-SG(SiO 2 ) catalyst (2.0 wt%) in water at 170 °C for 0.5 h. The catalytic mechanism of ChCl:OA-SG(SiO 2 )-catalyzed biomass into furfural was interpreted in the aqueous system. Corncob-valorized FF was wholly transformed to furfuryl alcohol with recombinant Escherichia coli CG-19 cells after bioreduction for 3 h of at 30 °C and pH 7.0. Yield of 0.416 g furfuryl alcohol/g xylan in corncob was obtained. This established hybrid catalysis could efficiently valorize biomass into value-added furfuryl alcohol.
研究领域:
生物化学
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催化化学
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可再生资源工程
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产品关联
DOI
高影响因子
Catalysts
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2021
·Vol. 11
·期 9
·1126
·
IF 4.146
Qingman Li,Qihua Jiang,Pengcheng Gu,Lianju Ma,Yiwu Wang
Ni2+-NTA-boosted magnetic porous silica nanoparticles (Ni@MSN) to serve as ideal support for bi-functional enzyme were fabricated for the first time. The versatility of this support was validated by one-step purification and immobilization of bi-functional enzyme MLG consisting of 3-Quinuclidinone reductase and glucose dehydrogenase, which can simultaneously catalyze both carbonyl reduction and cofactor regeneration, to fabricate an artificial bi-functional nanobiocatalyst (namely, MLG-Ni@MSN). The enzyme loading of 71.7 mg/g support and 92.7% immobilization efficiency were obtained. Moreover, the immobilized MLG showed wider pH and temperature tolerance and greater storage stability than free MLG under the same conditions. The nanosystem was employed as biocatalyst to accomplish the 3-quinuclidinone (70 g/L) to (R)-3-quinuclidinol biotransformation in 100% conversion yield with >99% selectivity within 6 h and simultaneous cofactor regeneration. Furthermore, the immobilized MLG retained up to 80.3% (carbonyl reduction) and 78.0% (cofactor regeneration) of the initial activity after being recycled eight times. In addition, the MLG-Ni@MSN system exhibited almost no enzyme leaching during biotransformation and recycling. Therefore, we have reason to believe that the Ni@MSN support gave great promise for constructing a new biocatalytic nanosystem with multifunctional enzymes to achieve some other complex bioconversions.Keywords:porous silica nanoparticles;immobilized enzyme;nanosystem;cofactor regeneration;(R)-3-quinuclidinol;biocatalysts’ recycling
研究领域:
生物工程
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酶学
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纳米技术
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合成生物学
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产品关联
DOI
高影响因子
BIOCATALYSIS AND BIOTRANSFORMATION
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2022
·
IF 2.325
Jian Yao,Lun Gui,Qizhang Long
Soil microbes are an abundant source of enzymes with unique properties that may be useful for industrial applications. As most wild-type strains show low chlorogenic acid esterase expression and activity, and most microbes cannot be cultured in the laboratory, a metagenomic approach provides methods of identifying new enzymes. In this study, a gene encoding a chlorogenic acid esterase, named Tan410, was isolated from a soil metagenomic library and overexpressed in Escherichia coli BL21 (DE3). The recombinant enzyme, with a predicted molecular weight of 54.88 kDa, was purified to homogeneity. The Km and Vmax values for Tan410 were 1.26 mM and 0.33 mM min–1, respectively, with chlorogenic acid as the substrate. Its optimum temperature and pH for reaction were 30 °C and 7.5, respectively. The enzyme exhibited moderate thermostability and broad pH stability (3.0–10.0). Tan410 was also able to hydrolyse ethyl ferulate, methyl caffeate, propyl gallate, ethyl gallate, methyl vanillate, methyl benzoate, ethyl benzoate, methyl 2,5-dihydroxybenzoate, and methyl 3,5-dihydroxybenzoate, and it released caffeic and ferulic acids from agricultural byproducts (destarched wheat bran and coffee pulp). Tan140 has potential for industrial application in biomass valorization.
研究领域:
生物化学
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环境微生物学
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工业酶学
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产品关联
DOI
高影响因子
ADVANCED MATERIALS
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2022
·Vol. 35
·期 9
·2208681
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IF 32.086
Congyang Mao,Wanyu Jin,Yiming Xiang,Yizhou Zhu,Jun Wu,Xiangmei Liu,Shuilin Wu,Yufeng Zheng,Kenneth M. C. Cheung,Kelvin Wai Kwok Yeung
Conferring catalytic defects in sonosensitizers is of paramount importance in reinforcing sonodynamic therapy. However, the formation of such 0D defects is governed by the Schottky defect principle. Herein, 2D catalytic planar defects are designed within Ti 3 C 2 sheets to address this challenge. These specific planar slip dislocations with abundant Ti 3+ species (Ti 3 C 2 -SD(Ti 3+ )) can yield surface-bound O due to the effective activation of O 2 , thus resulting in a substantial amount of 1 O 2 generation and the 99.72% ± 0.03% bactericidal capability subject to ultrasound (US) stimulation. It is discovered that the 2D catalytic planar defects can intervene in electron transfer through the phonon drag effect—a coupling effect between surface electrons and US-triggered phonons—that simultaneously contributes to a dramatic decrease in O 2 activation energy from 1.65 to 0.06 eV. This design has achieved a qualitative leap in which the US catalytic site has transformed from 0D to 2D. Moreover, it is revealed that the electron origin, electron transfer, and visible O 2 activation pathway triggered by US can be attributed to the phonon–electron coupling effect. After coating with neutrophil membrane (NM) proteins, the NM-Ti 3 C 2 -SD(Ti 3+ ) sheets further demonstrate a 6-log 10 reduction in methicillin-resistant Staphylococcus aureus burden in the infected bony tissue.
研究领域:
材料科学
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纳米技术
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生物医学工程
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微生物学
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF CONTROLLED RELEASE
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2022
·
IF 11.467
Baizhu Chen,Xiaoge Zhang,Lili Cheng,Xiaomei Chen,Junjie Tang,Peng Zhang,Chen Wang,Jie Liu
The use of bacteria as living vehicles has attracted increasing attentions in tumor therapy field. The combination of functional materials with bacteria dramatically facilitates the antitumor effect. Here, we presented a rationally designed living system formed by programmed Escherichia Coli MG1655 cells (Ec) and black phosphorus (BP) nanoparticles (NPs). The bacteria were genetically engineered to express tumor necrosis factor-related apoptosis-inducing ligand (TRAIL), via an outer membrane YiaT protein (Ec-T). The Ec-T cells were associated with BP NPs on their surface to acquire [email protected] The designed living system could transfer the photoelectrons produced by BP NPs after laser irradiation and triggered the reductive metabolism of nitrate to nitric oxide for the in situ release at tumor sites, facilitating the therapeutic efficacy and the polarization of tumor associated macrophages to M1 phenotype. Meanwhile, the generation of reactive oxygen species induced the immunogenic cell death to further improve the antitumor efficacy. Additionally, the living system enhanced the immunological effect by promoting the apoptosis of tumor cells, activating the effect of T lymphocytes and releasing the pro-inflammatory cytokines. The integration of BP NPs, MG1655 cells and TRAIL led to an effective tumor therapy. Our work established an approach for the multifunctional antitumor living therapy.
研究领域:
癌症治疗
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生物医学工程
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纳米技术
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免疫学
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分子生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Cell Host & Microbe
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2022
·
IF 31.316
Zhen-Ping Zou,Yue Du,Ting-Ting Fang,Ying Zhou,Bang-Ce Ye
Summary Rapid advances in synthetic biology have fueled interest in engineered microorganisms that can diagnose and treat disease. However, designing bacteria that detect dynamic disease-associated biomarkers that then drive treatment remains difficult. Here, we have developed an engineered probiotic that noninvasively monitors and records inflammatory bowel disease (IBD) occurrence and progression in real time and can release treatments via a self-tunable mechanism in response to these biomarkers. These intelligent responsive bacteria for diagnosis and therapy (i-ROBOT) consists of E. coli Nissle 1917 that responds to levels of the inflammatory marker thiosulfate by activating a base-editing system to generate a heritable genomic DNA sequence as well as producing a colorimetric signal. Fluctuations in thiosulfate also drive the tunable release of the immunomodulator AvCystatin . Orally administering i-ROBOT to mice with colitis generated molecular recording signals in processed fecal and colon samples and effectively ameliorated disease. i-ROBOT provides a promising paradigm for gastrointestinal and other metabolic disorders.
研究领域:
合成生物学
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微生物学
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胃肠病学
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分子生物学
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产品关联
DOI
PubMed
高影响因子
Microbial Biotechnology
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2023
·
IF 5.7
Xinyue Ye,Jian Wang,Pengfei Xu,Xiaoqian Yang,Qixue Shi,Genyan Liu,Zhaoshi Bai,Changlin Zhou,Lingman Ma
Polymyxin resistance is conferred by MCR-1 (mobile colistin resistance 1)-induced lipopolysaccharide (LPS) modification of G − bacteria. However, the peptide MSI-1 exerts potent antimicrobial activity against mcr-1 -carrying bacteria . To further investigate the potential role of MCR-1 in improving bacterial virulence and facilitating immune evasion, and the immunomodulatory effect of peptide MSI-1, we first explored outer membrane vesicle (OMV) alterations of mcr-1 -carrying bacteria in the presence and absence of sub-MIC MSI-1, and host immune activation during bacterial infection and OMV stimulation. Our results demonstrated that LPS remodelling induced by MCR-1 negatively affected OMV formation and protein cargo by E. coli . In addition, MCR-1 diminished LPS-stimulated pyroptosis but facilitated mitochondrial dysfunction, further aggravating apoptosis in macrophages induced by OMVs of E. coli . Similarly, TLR4-mediated NF-κB activation was markedly alleviated once LPS was modified by MCR-1. However, peptide MSI-1 at the sub-MIC level inhibited the expression of MCR-1, further partly rescuing OMV alteration and attenuation of immune responses in the presence of MCR-1 during both infection and OMV stimulation, which can be exploited for anti-infective therapy.
研究领域:
微生物学
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免疫学
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药理学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Materials Chemistry B
·
2023
·
IF 7
Jianan Li,Wenjie Huang,Huixia He,Shuangni Shi,Xiuxia Sun,Jianxi Xiao
Prolonged exposure to UV radiation can cause severe photodamage to the skin, leading to abnormal fragmentation of elastin fibers. As one of the main protein components of the dermal extracellular matrix, elastin plays a critical role in the mechanical behavior and physiological function of the skin. Animal-derived elastin has attracted extensive attention in tissue engineering, however it suffers from severe drawbacks such as a risk of virus transmission, ready degradation, and challenging quality control. Herein, we have for the first time developed a novel recombinant fusion elastin (RFE) and its cross-linked hydrogel for improved healing efficacy for UV-irradiated skin. RFE showed temperature-sensitive aggregation behavior similar to natural elastin. Compared with recombinant elastin without the fusion V-foldon domain, RFE showed a much more ordered secondary structure and lower transition temperature. Furthermore, Native-PAGE results indicated that the addition of the V-foldon domain triggered the formation of remarkable oligomers in RFE, which may result in a more ordered conformation. Tetrakis Hydroxymethyl Phosphonium Chloride (THPC) cross-linking of RFE led to the production of a fibrous hydrogel with uniform three-dimensional porous nanostructures and excellent mechanical strength. The RFE hydrogel showed superior cellular activity, significantly promoting the survival and proliferation of human foreskin fibroblast-1 (HFF-1). Studies of mice models of UV-irradiated skin demonstrated that the RFE hydrogel pronouncedly accelerated their healing process by inhibiting epidermal hyperplasia as well as boosting the regeneration of collagen and elastin fibers. The highly biocompatible and bioactive recombinant fusion elastin and its cross-linked hydrogel provide a potent treatment for photodamaged skin, which may have promising applications in dermatology and tissue engineering.
研究领域:
组织工程
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皮肤病学
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生物材料
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生物医学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Algal Research-Biomass Biofuels and Bioproducts
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2022
·
IF 5.276
Tiancheng Tang,Benwei Zhu,Zhong Yao
Ulvan , extracted from the marine green algae belonging to the genus Ulva , is a complex water-soluble sulfated polysaccharide which mainly composed of four monosaccharides consisting of rhamnose , xylose , glucuronic acid and iduronic acid . Its complex monosaccharide composition gives ulvan great potential for application in the fields of food, pharmaceuticals, and chemistry. And it can be degraded by ulvan lyases mainly from Polysaccharide Lyases (PL) family of PL24, PL25 and PL28 through β -elimination mechanism, which cleaves the β -glycosidic bond between sulfated rhamnose and glucuronic acid or iduronic acid, thereby producing an Ulva oligosaccharide with unsaturated bond. In this study, we have identified a putative ulvan lyase from Alteromonas sp. TK-45 (2). We heterologously expressed, purified, and biochemically characterized the ulvan lyase, which has removed signal peptide . The results show that ULA-1 had best activity at 45 °C and pH 8.0. The K m and V max values were 13.25 μg·mL −1 and 1.719 μmol·min −1 ·mL −1 , respectively. The thermostability of ULA-1 was excellent, and its activity hardly decreased after incubation at 45 °C for 1 h. ESI-MS analysis showed that the primary end-product were disaccharides to tetrasaccharides . In conclusion, our research has expanded the database of ulvan lyase, and provided the possibility to make full use of ulvan, a huge marine biomass resource .
研究领域:
海洋生物学
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酶学
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生物技术
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生物化学
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产品关联
DOI
高影响因子
PROCESS BIOCHEMISTRY
·
2023
·
IF 4.4
Chenchen Zhao,Yu Sha,Wei Zhuang,Yuan Rao,Jihang Zhang,Jinglan Wu,Tao Shen,Zhuotao Tan,Chenjie Zhu,Hongman Zhang,Hanjie Ying
Hydroxytyrosol (HT) is a novel functional pharmaceutical or food ingredient that can be prepared using tyrosinase (TYR) as the catalyst. In this study, cross-linked agarose resin (AG-NTA-Ni 2+ ) was selected as the carrier for the one-step immobilization and purification of the enzyme via specific adsorption of the His-tag on the protein and metal ions on the carrier particles. The immobilized TYR exhibited excellent thermal and pH stabilities and retained 82.3% of its relative activity after seven cycles. Using different reduction methods, immobilized TYR was used as a catalyst to synthesize HT via the controlled oxidation of tyrosol. The enzymatic cascade reaction of co-immobilized TYR and glucose dehydrogenase (GDH) as a biocatalyst served as a bioreduction method with an HT yield of 88%. For the chemical reduction using ascorbic acid (AA) as the reducing agent, an 80% HT yield was achieved. These results indicate that the immobilization method, which relies on the specific coordination between transition metal ions and certain protein amino acids , is a potential strategy for the effective co-immobilization of TYR and GDH. The proposed affinity co-immobilization technique is among the potential strategies for the efficient production of HT.
研究领域:
生物技术
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酶学
·
药学
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食品科学
✓ 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）