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Cofactor engineering in cyanobacteria to overcome imbalance between NADPH and NADH: A mini review

Jongmoon Park,Yunnam Choi

《化学科学与工程前沿（英文）》 2017年 第11卷 第1期   页码 66-71 doi: 10.1007/s11705-016-1591-1

摘要： Cyanobacteria can produce useful renewable fuels and high-value chemicals using sunlight and atmospheric carbon dioxide by photosynthesis. Genetic manipulation has increased the variety of chemicals that cyanobacteria can produce. However, their uniquely abundant NADPH-pool, in other words insufficient supply of NADH, tends to limit their production yields in case of utilizing NADH-dependent enzyme, which is quite common in heterotrophic microbes. To overcome this cofactor imbalance and enhance cyanobacterial fuel and chemical production, various approaches for cofactor engineering have been employed. In this review, we focus on three approaches: (1) utilization of NADPH-dependent enzymes, (2) increasing NADH production, and (3) changing cofactor specificity of NADH-dependent enzymes from NADH to NADPH.

关键词： NADH-dependent enzyme     NADPH-dependent enzyme     transhydrogenase     site-directed mutagenesis     enzyme engineering    

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Designer enzyme for green materials innovation: Lactate-polymerizing enzyme as a key catalyst

Seiichi Taguchi

《化学科学与工程前沿（英文）》 2017年 第11卷 第1期   页码 139-142 doi: 10.1007/s11705-017-1636-0

摘要： Establishment of the regeneratable whole-cell catalyst platform for the?production of biobased polymeric materials is a?typical topic of synthetic biology. In this commentary, discovery story of a “lactate-polymerizing enzyme” (LPE)?and LPE-based?achievements for creating a new variety of polyesters with incorporated unnatural monomers are presented. Besides the importance of microbial platform itself is discussed referring to the “ballooning”- .

关键词： synthetic biology     enzyme evolutionary engineering     polyhydroxyalkanoate    

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Influence of glucose feeding on the ligninolytic enzyme production of the white-rot fungus Phanerochaete

ZHOU Xiaoyan, WEN Xianghua, FENG Yan

《环境科学与工程前沿（英文）》 2007年 第1卷 第1期   页码 89-94 doi: 10.1007/s11783-007-0017-1

摘要： The present work studied the influence of glucose feeding on the ligninolytic enzyme production of in a nitrogen-limited (C/N ratio is 56/8.8 mmol/L) medium. Several sets of shaking flask experiments were conducted. The results showed that 2 g/L glucose feeding on the first day of the culture (24 h after the inoculation) stimulated both fungal biomass growth and enzyme production. The manganese peroxidase (MnP) activity was 2.5 times greater than that produced in cultures without glucose feeding. Furthermore, the glucose feeding mode in fed-batch culture was also investigated. Compared to cultures with glucose feeding every 48 h, cultures with glucose feeding of 1.5 g/L (final concentration) every 24 h produced more enzymes. The peak and total yield of MnP activity were 2.7 and 3 times greater compared to the contrast culture, respectively, and the enzyme was kept stable for 4 days with an activity of over 200 U/L.

关键词： enzyme production     fed-batch culture     nitrogen-limited     inoculation     mmol/L    

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Diffusion process in enzyme–metal hybrid catalysts

《化学科学与工程前沿（英文）》 2022年 第16卷 第6期   页码 921-929 doi: 10.1007/s11705-022-2144-4

摘要： Enzyme–metal hybrid catalysts bridge the gap between enzymatic and heterogeneous catalysis, which is significant for expanding biocatalysis to a broader scope. Previous studies have demonstrated that the enzyme–metal hybrid catalysts exhibited considerably higher catalytic efficiency in cascade reactions, compared with that of the combination of separated enzyme and metal catalysts. However, the precise mechanism of this phenomenon remains unclear. Here, we investigated the diffusion process in enzyme–metal hybrid catalysts using Pd/lipase-Pluronic conjugates and the combination of immobilized lipase (Novozyme 435) and Pd/C as models. With reference to experimental data in previous studies, the Weisz–Prater parameter and efficiency factor of internal diffusion were calculated to evaluate the internal diffusion limitations in these catalysts. Thereafter, a kinetic model was developed and fitted to describe the proximity effect in hybrid catalysts. Results indicated that the enhanced catalytic efficiency of hybrid catalysts may arise from the decreased internal diffusion limitation, size effect of Pd clusters and proximity of the enzyme and metal active sites, which provides a theoretical foundation for the rational design of enzyme–metal hybrid catalysts.

关键词： enzyme–metal hybrid catalyst     internal diffusion     proximity effect     kinetic model    

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Detection of Escherichia coli in wastewater based on enzyme immunoassay

XI Haiyan, CAI Qiang, HE Miao, SHI Hanchang

《环境科学与工程前沿（英文）》 2007年 第1卷 第3期   页码 381-384 doi: 10.1007/s11783-007-0065-6

摘要： This research describes a fast detection method on the basis of enzyme-linked immunosorbent assay (ELISA) for in drainage of wastewater treatment plants. Optimized conditions such as the reaction format (sandwich or direct), the concentrations of diluted horse radish peroxidase (HRP)- conjugate, and anti-HPR antibody and pretreatment of were studied. Those results showed that the linear range of detection for was 10 cfu/mL– 6 × 10 cfu/mL. Compared with conventional methods, it is a convenient and sensitive detection method with low cost.

关键词： conventional     sandwich     pretreatment     enzyme-linked immunosorbent     detection    

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Enzyme@bismuth-ellagic acid: a versatile platform for enzyme immobilization with enhanced acid-base stability

《化学科学与工程前沿（英文）》 2023年 第17卷 第6期   页码 784-794 doi: 10.1007/s11705-022-2278-4

摘要： In situ encapsulation is an effective way to synthesize enzyme@metal–organic framework biocatalysts; however, it is limited by the conditions of metal–organic framework synthesis and its acid-base stability. Herein, a biocatalytic platform with improved acid-base stability was constructed via a one-pot method using bismuth-ellagic acid as the carrier. Bismuth-ellagic acid is a green phenol-based metal–organic framework whose organic precursor is extracted from natural plants. After encapsulation, the stability, especially the acid-base stability, of amyloglucosidases@bismuth-ellagic acid was enhanced, which remained stable over a wide pH range (2–12) and achieved multiple recycling. By selecting a suitable buffer, bismuth-ellagic acid can encapsulate different types of enzymes and enable interactions between the encapsulated enzymes and cofactors, as well as between multiple enzymes. The green precursor, simple and convenient preparation process provided a versatile strategy for enzymes encapsulation.

关键词： bismuth-ellagic acid     in situ encapsulation     enzyme@MOF biocomposites    

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Soil enzyme activities and their indication for fertility of urban forest soil

SHAN Qihua, YU Yuanchun, ZHANG Jinchi, YU Jian

《环境科学与工程前沿（英文）》 2008年 第2卷 第2期   页码 218-223 doi: 10.1007/s11783-008-0037-5

摘要： To reveal the biological characteristics of urban forest soil and the effects of soil enzyme on soil fertility as well as the correlation between physicochemical properties and enzyme activities, 44 urban forest soil profiles in Nanjing were investigated. Basic soil physicochemical properties and enzyme activities were analyzed in the laboratory. Hydrogen peroxidase, dehydrogenase, alkaline phosphatase, and cellulase were determined by potassium permanganate titration, TTC (CHN·Cl) colorimetry, phenyl phosphate dinatrium colorimetry, and anthrone colorimetry, respectively. The result showed that soil pH, organic carbon (C), and total nitrogen (N) had great effects on hydrogen peroxidase, dehydrogenase, and alkaline phosphatase activities in 0–20 cm thick soil. However, pH only had great effect on hydrogen peroxidase, dehydrogenase, and alkaline phosphatase activities in 20–40 cm thick soil. Hydrogen peroxidase, dehydrogenase, and alkaline phosphatase were important biological indicators for the fertility of urban forest soil. Both in 0–20 cm and 20–40 cm soil, soil enzyme system (hydrogen peroxidase, dehydrogenase, alkaline phosphatase, and cellulase) had a close relationship with a combination of physicochemical indicators (pH, organic C, total N, available K, available P, cation exchange capacity (CEC), and microbial biomass carbon (C)). The more soil enzyme activities there were, the higher the fertility of urban forest soil.
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Data-driven approach to solve vertical drain under time-dependent loading

《结构与土木工程前沿（英文）》 2021年 第15卷 第3期   页码 696-711 doi: 10.1007/s11709-021-0727-7

摘要： Currently, the vertical drain consolidation problem is solved by numerous analytical solutions, such as time-dependent solutions and linear or parabolic radial drainage in the smear zone, and no artificial intelligence (AI) approach has been applied. Thus, in this study, a new hybrid model based on deep neural networks (DNNs), particle swarm optimization (PSO), and genetic algorithms (GAs) is proposed to solve this problem. The DNN can effectively simulate any sophisticated equation, and the PSO and GA can optimize the selected DNN and improve the performance of the prediction model. In the present study, analytical solutions to vertical drains in the literature are incorporated into the DNN–PSO and DNN–GA prediction models with three different radial drainage patterns in the smear zone under time-dependent loading. The verification performed with analytical solutions and measurements from three full-scale embankment tests revealed promising applications of the proposed approach.

关键词： vertical drain     artificial neural network     time-dependent loading     deep learning network     genetic algorithm     particle swarm optimization    

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Chloride binding and time-dependent surface chloride content models for fly ash concrete

S. MUTHULINGAM,B. N. RAO

《结构与土木工程前沿（英文）》 2016年 第10卷 第1期   页码 112-120 doi: 10.1007/s11709-015-0322-x

摘要： Corrosion of embedded rebars is a classical deterioration mechanism of reinforced concrete structures exposed to chloride environments. Such environments can be attributed to the presence of seawater, deicing or sea-salts, which have high concentrations of chloride ion. Chloride ingress into concrete, essential for inducing rebar corrosion, is a complex interaction between many physical and chemical processes. The current study proposes two chloride ingress parameter models for fly ash concrete, namely: 1) surface chloride content under tidal exposure condition; and 2) chloride binding. First, inconsistencies in surface chloride content and chloride binding models reported in literature, due to them not being in line with past research studies, are pointed out. Secondly, to avoid such inconsistencies, surface chloride content and chloride binding models for fly ash concrete are proposed based upon the experimental work done by other researchers. It is observed that, proposed models are simple, consistent and in line with past research studies reported in literature.

关键词： binding isotherms     chloride ingress     concrete     fly ash     surface chloride content    

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Plant diversity reduces the effect of multiple heavy metal pollution on soil enzyme activities and microbial

Yang GAO, Chiyuan MIAO, Jun XIA, Liang MAO, Yafeng WANG, Pei ZHOU

《环境科学与工程前沿（英文）》 2012年 第6卷 第2期   页码 213-223 doi: 10.1007/s11783-011-0345-z

摘要： It is unclear whether certain plant species and plant diversity could reduce the impacts of multiple heavy metal pollution on soil microbial structure and soil enzyme activities. Random amplified polymorphic DNA (RAPD) was used to analyze the genetic diversity and microbial similarity in planted and unplanted soil under combined cadmium (Cd) and lead (Pb) pollution. A metal hyperaccumulator, , and a common plant, , were used in this research. The results showed that microorganism quantity in planted soil significantly increased, compared with that in unplanted soil with Cd and Pb pollution. The order of microbial community sensitivity in response to Cd and Pb stress was as follows: actinomycetes>bacteria>fungi. Respiration, phosphatase, urease and dehydrogenase activity were significantly inhibited due to Cd and Pb stress. Compared with unplanted soil, planted soils have frequently been reported to have higher rates of microbial activity due to the presence of additional surfaces for microbial colonization and organic compounds released by the plant roots. Two coexisting plants could increase microbe population and the activity of phosphatases, dehydrogenases and, in particular, ureases. Soil enzyme activity was higher in phytoremediated soil than in planted soil in this study. Heavy metal pollution decreased the richness of the soil microbial community, but plant diversity increased DNA sequence diversity and maintained DNA sequence diversity at high levels. The genetic polymorphism under heavy metal stress was higher in phytoremediated soil than in planted soil.

关键词： enzyme activity     soil DNA     microbial population     plant diversity     heavy metal    

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GDF15 negatively regulates chemosensitivity via TGFBR2-AKT pathway-dependent metabolism in esophageal

《医学前沿（英文）》 2023年 第17卷 第1期   页码 119-131 doi: 10.1007/s11684-022-0949-7

摘要： Treating patients with esophageal squamous cell carcinoma (ESCC) is challenging due to the high chemoresistance. Growth differentiation factor 15 (GDF15) is crucial in the development of various types of tumors and negatively related to the prognosis of ESCC patients according to our previous research. In this study, the link between GDF15 and chemotherapy resistance in ESCC was further explored. The relationship between GDF15 and the chemotherapy response was investigated through in vitro and in vivo studies. ESCC patients with high levels of GDF15 expression showed an inferior chemotherapeutic response. GDF15 improved the tolerance of ESCC cell lines to low-dose cisplatin by regulating AKT phosphorylation via TGFBR2. Through an in vivo study, we further validated that the anti-GDF15 antibody improved the tumor inhibition effect of cisplatin. Metabolomics showed that GDF15 could alter cellular metabolism and enhance the expression of UGT1A. AKT and TGFBR2 inhibition resulted in the reversal of the GDF15-induced expression of UGT1A, indicating that TGFBR2-AKT pathway-dependent metabolic pathways were involved in the resistance of ESCC cells to cisplatin. The present investigation suggests that a high level of GDF15 expression leads to ESCC chemoresistance and that GDF15 can be targeted during chemotherapy, resulting in beneficial therapeutic outcomes.

关键词： GDF15     esophageal squamous cell carcinoma     chemoresistance     cellular metabolism     TGFBR2     AKT    

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Analysis of dispatching rules in a stochastic dynamic job shop manufacturing system with sequence-dependent

Pankaj SHARMA,Ajai JAIN

《机械工程前沿（英文）》 2014年 第9卷 第4期   页码 380-389 doi: 10.1007/s11465-014-0315-9

摘要：

Stochastic dynamic job shop scheduling problem with consideration of sequence-dependent setup times are among the most difficult classes of scheduling problems. This paper assesses the performance of nine dispatching rules in such shop from makespan, mean flow time, maximum flow time, mean tardiness, maximum tardiness, number of tardy jobs, total setups and mean setup time performance measures viewpoint. A discrete event simulation model of a stochastic dynamic job shop manufacturing system is developed for investigation purpose. Nine dispatching rules identified from literature are incorporated in the simulation model. The simulation experiments are conducted under due date tightness factor of 3, shop utilization percentage of 90 % and setup times less than processing times. Results indicate that shortest setup time (SIMSET) rule provides the best performance for mean flow time and number of tardy jobs measures. The job with similar setup and modified earliest due date (JMEDD) rule provides the best performance for makespan, maximum flow time, mean tardiness, maximum tardiness, total setups and mean setup time measures.

关键词： scheduling     stochastic dynamic job shop     sequence-dependent setup times     dispatching rule     simulation    

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Degradation of 4-aminophenol by hydrogen peroxide oxidation using enzyme from Serratia marcescens as

SUN Min, YOU Yahua, DENG Shengsong, GAO Wenxia, YAO Risheng

《环境科学与工程前沿（英文）》 2007年 第1卷 第1期   页码 95-98 doi: 10.1007/s11783-007-0018-0

摘要： AB 90027 as catalyst. The effecting factors during degradation and the degrading mechanism were studied. Also, the location of the enzyme in the cell, which could catalyze the degradation of 4-aminophenol, was analyzed. The results showed that to degrade 50 mL of 4-aminophenol whose concentration was 500 mg/L, the optimal conditions were: volume of HO = 3 mL, temperature = 40 60?C and pH = 9 10. In the degradation process, 4-aminophenol was first converted to benzoquinone and NH, then organic acids including maleic acid, fumaleic acid, and oxalic acid were formed, and then finally CO and HO were generated as final products. The enzyme that could catalyze the degradation of 4-aminophenol was mainly extracellular enzyme.

关键词： degradation process     temperature     effecting     degradation     volume    

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NADPH oxidase and reactive oxygen species as signaling molecules in carcinogenesis

Gang WANG

《医学前沿（英文）》 2009年 第3卷 第1期   页码 1-7 doi: 10.1007/s11684-009-0018-5

摘要： Reactive oxygen species (ROS) are small molecule metabolites of oxygen that are prone to participate in redox reactions their high reactivity. Intracellular ROS could be generated in reduced nicotinamide-adenine dinucleotidephosphate (NADPH) oxidase-dependent and/or NADPH oxidase-independent manners. Physiologically, ROS are involved in many signaling cascades that contribute to normal processes. One classical example is that ROS derived from the NADPH oxidase and released in neurotrophils are able to digest invading bacteria. Excessive ROS, however, contribute to pathogenesis of various human diseases including cancer, aging, dimentia and hypertension. As signaling messengers, ROS are able to oxidize many targets such as DNA, proteins and lipids, which may be linked with tumor growth, invasion or metastasis. The present review summarizes recent advances in our comprehensive understanding of ROS-linked signaling pathways in regulation of tumor growth, invasion and metastasis, and focuses on the role of the NADPH oxidase-derived ROS in cancer pathogenesis.

关键词： free radicals     tumor     phox     cell proliferation     cancer therapy    

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Microcystin-LR detection based on indirect competitive enzyme-linked immunosorbent assay

SHENG Jianwu, HE Miao, YU Shaoqing, SHI Hanchang, QIAN Yi

《环境科学与工程前沿（英文）》 2007年 第1卷 第3期   页码 329-333 doi: 10.1007/s11783-007-0056-7

摘要： Microcystins (MCs) are a group of closely related toxic cyclic heptapeptides produced by common cyanobacteria, which cause lots of accidents and threatens human health. In this paper, an indirect competitive enzyme-linked immunosorbent assay (ic-ELISA) was established and used to detect microcystin-LR (MC-LR) in drinking and surface waters. The concentration of coating antigen was 5 ?g/mL, the dilution of monoclonal antibody MC10E7 was 1:3 000, the dilution of enzyme tracer (goat anti-mouse IgG-peroxidase) was 1:3 000, the standard concentration of MC-LR ranged from 0.001 μg/L to 30 μg/L, and o-phenylenediamine was used as substrate. The assay showed high relativity with high performance liquid chromatography (HPLC) with a correlation coefficient of more than 99%. The relative standard deviation was less than 10%, the detection limit was achieved down to 0.01 μg/L and up to 5.1 μg/L. The quantitative detection range was from 0.03 μg/L to 3 μg/L, and the antibody had high specificity for [4-arginine] microcystins. It performed well in spite of the influence of the real samples.

关键词： o-phenylenediamine     4-arginine     ic-ELISA     substrate     chromatography    

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标题 作者 时间 类型 操作

Cofactor engineering in cyanobacteria to overcome imbalance between NADPH and NADH: A mini review

Jongmoon Park,Yunnam Choi

期刊论文

Designer enzyme for green materials innovation: Lactate-polymerizing enzyme as a key catalyst

Seiichi Taguchi

期刊论文

Influence of glucose feeding on the ligninolytic enzyme production of the white-rot fungus Phanerochaete

ZHOU Xiaoyan, WEN Xianghua, FENG Yan

期刊论文

Diffusion process in enzyme–metal hybrid catalysts

期刊论文

Detection of Escherichia coli in wastewater based on enzyme immunoassay

XI Haiyan, CAI Qiang, HE Miao, SHI Hanchang

期刊论文

Enzyme@bismuth-ellagic acid: a versatile platform for enzyme immobilization with enhanced acid-base stability

期刊论文

Soil enzyme activities and their indication for fertility of urban forest soil

SHAN Qihua, YU Yuanchun, ZHANG Jinchi, YU Jian

期刊论文

Data-driven approach to solve vertical drain under time-dependent loading

期刊论文

Chloride binding and time-dependent surface chloride content models for fly ash concrete

S. MUTHULINGAM,B. N. RAO

期刊论文

Plant diversity reduces the effect of multiple heavy metal pollution on soil enzyme activities and microbial

Yang GAO, Chiyuan MIAO, Jun XIA, Liang MAO, Yafeng WANG, Pei ZHOU

期刊论文

GDF15 negatively regulates chemosensitivity via TGFBR2-AKT pathway-dependent metabolism in esophageal

期刊论文

Analysis of dispatching rules in a stochastic dynamic job shop manufacturing system with sequence-dependent

Pankaj SHARMA,Ajai JAIN

期刊论文

Degradation of 4-aminophenol by hydrogen peroxide oxidation using enzyme from Serratia marcescens as

SUN Min, YOU Yahua, DENG Shengsong, GAO Wenxia, YAO Risheng

期刊论文

NADPH oxidase and reactive oxygen species as signaling molecules in carcinogenesis

Gang WANG

期刊论文

Microcystin-LR detection based on indirect competitive enzyme-linked immunosorbent assay

SHENG Jianwu, HE Miao, YU Shaoqing, SHI Hanchang, QIAN Yi

期刊论文