APPLIED AND ENVIRONMENTAL MICROBIOLOGY
·
2023
·Vol. 89
·期 4
·
IF 4.4
Xuling Jiang,Wanqing Wei,Yaozhong Cui,Wei Song,Yingying Li,Xiulai Chen,Cong Gao,Jia Liu,Liang Guo,Liming Liu,Jing Wu
Pyrrolidone is a high value-added monomer and an important active drug intermediate. However, the efficient enzymatic synthesis of pyrrolidone remains a challenge. Here, we developed and reconstructed a three-enzyme cascade pathway using Escherichia coli BL21(DE3) for the production of pyrrolidone from l-glutamate (l-Glu). The carnitine-CoA ligase from Escherichia coli (EcCaiC) at a low expression level and with a low activity is regarded as the rate-limiting enzyme. Here, we obtained the best EcCaiCF380M/N430D double mutant with a kcat/Km value 1.5 times higher than that of the wild type via mechanism-based protein engineering. For this, we (i) eliminated the steric hindrance of the loop ring to improve the precatalytic conformation of the adenylation intermediate and (ii) fixed the hinge region to stabilize the closed conformation of the enzyme. Furthermore, ribosome-binding site (RBS) optimization led to an increase in the expression level of EcCaiCF380M/N430D, which was then cloned into the plasmid pET-EcCaiCF380M/N430D-DegoPPK2. Finally, under optimal induction and transformation conditions, 16.62 g/L of pyrrolidone was generated from 30 g/L l-Glu (batch feeding) within 24 h with a molar conversion rate of 95.2% and the highest productivity ever obtained, to our knowledge (0.69 g/L/h). Our findings demonstrate a strategy that is potentially attractive for the industrial production of pyrrolidone.IMPORTANCE This study developed a three-enzyme cascade pathway for the production of pyrrolidone from l-Glu. The catalytic efficiency of carnitine CoA ligase from Escherichia coli (EcCaiC) was improved by mechanism-based protein engineering, and the titer of pyrrolidone was further increased by ribosome-binding site (RBS), induction conditions, and conversion conditions optimization. Finally, we efficiently produced pyrrolidone by one pot in vivo with 95.2% conversion and 0.69 g/L/h productivity. Our study provides a new possibility for the industrial production of enzymatic synthesis of pyrrolidone.
研究领域:
生物化学
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合成生物学
·
酶工程
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DOI
PubMed
高影响因子
CHEMICAL ENGINEERING & TECHNOLOGY
·
2022
·Vol. 46
·期 2
·383-389
·
IF 2.215
Hui Yang,Dan Wang,Jun Gao,Lianzheng Zhang,Tao Zhang,Dongmei Xu,Yinglong Wang
To reduce emission of nitrogen oxides (NO x ) mainly produced from the combustion of nitrogen compounds (NCs) in fossil fuels, it is necessary to decrease the NCs content in fossil fuels. 2-Pyrrolidone-based protic ionic liquids (PrILs) with three different anions were synthesized by a one-step method. The three PrILs were used as extractants to extract pyridine from the model mixtures. The extraction efficiency ( EE ) was considered to evaluate the extraction performance of the PrILs. The interactions between the PrILs and pyridine were analyzed by σ-profiles, bond length, and deformation charge density. The results show that the hydrogen bond (H-bond) formed between pyridine and the three PrILs is the main driving force for the extraction of pyridine from the model mixtures.
研究领域:
能源化学
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环境科学
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产品关联
DOI
高影响因子
JOURNAL OF CHEMICAL AND ENGINEERING DATA
·
2025
·
IF 2.1
Jing Xia,Zhigao Sun
Additives are often used to solve the problem of hydrate blockage in pipelines such as carbon dioxide transportation and oil and gas transportation. Thermodynamic inhibitors can enhance the pressures of the hydrate phase equilibrium. The effect of 2-pyrrolidone on the CO2 hydrate phase equilibrium is investigated in this work. The experimental results indicate that 2-pyrrolidone may act as a thermodynamic inhibitor. 2-Pyrrolidone is a type of cyclic amide substance that contains polar functional groups such as carbonyl groups in its molecular structure. It is bound to water by hydrogen bonds, intensifying competition for water molecules and thereby inhibiting hydrate formation. Its inhibitory influence increases when the mass fraction of 2-pyrrolidone increases.
研究领域:
化学工程
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能源科学
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产品关联
DOI
高影响因子
POLYMER DEGRADATION AND STABILITY
·
2025
·
IF 7.4
Weiqi Chen,Hanxu Zhu,Han Hu,Qingyang Luan,Qi Jiang,Peng Liang,Linyi Hu,Jie Feng,Jinggang Wang,Jin Zhu
Most degradable polymers are utilized in applications below 100°C. Developing materials with high thermal performance (specifically high glass transition temperature) is critical to expanding their application range. Here, N,N′-trans-1,4-cyclohexane-bis (pyrrolidone-4-methyl carboxylate) (T-CBPMC), a tricyclic diester, was prepared via Michael addition-cyclization of renewable feedstocks and further used as a monomer to synthesize poly (ethylene-co-cyclohexanedimethylene-1,4-cyclohexane-bis (pyrrolidone-4-methyl carboxylate)) (PECP) copolyesters, with 1,4-cyclohexanedimethanol (CHDM) molar content ranging from 0% to 95% relative to the total diol. The copolymerization of ethylene glycol (EG) significantly accelerated chain length, yielding PECP copolyesters with number average molecular weight (M n ) ranging from 29.1 kDa to 48.4 kDa. The T-CBPMC units effectively enhanced the glass transition temperature (119-133°C) and crystallization property of PECP, endowing it with superior thermal properties. Furthermore, the pyrrolidone ring exhibits outstanding ultraviolet shielding efficacy. Despite their steric hindrance, pyrrolidone rings also conferred hydrophilicity to the polymer. PECP copolymers exhibited adjustable hydrolysis rate at room temperature, by varying the CP compositions, with weight loss varying from 5% to 68% after 60 days. Structural, morphological, and molecular weight analyses after hydrolysis revealed that cleavage preferentially occurred at the ester bonds linking T-CBPMC and EG. Combining rigid T-CBPMC and CHDM with EG provided a better balance, the CP segments enhanced the T g and crystallization capabilities of the polyester, whereas the EP segments imparted hydrolysability.
研究领域:
材料科学
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高分子化学
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产品关联
DOI
高影响因子
JOURNAL OF POWER SOURCES
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2023
·
IF 9.2
Yu Bai,Dongmei Han,Min Xiao,Zhiheng Huang,Chengxin Wang,Shuanjin Wang,Yuezhong Meng
Polypyrrolone (PPy) possesses excellent heat resistance and mechanical properties , moreover, the N-heterocycle contained in the PPy allows the absorption of phosphoric acid (PA) for proton conduction. In the present work, PPy is synthesized by a two-step method and evaluated for the first time as the polymeric material for high temperature proton exchange membranes (HT-PEMs). The PA-doped PPy membrane reaches a peak power density of 582 mW cm −2 at 160 °C under fully anhydrous conditions, besides, the fuel cell exhibits excellent durability over a period of 300 h with a load voltage decay of only 0.032% per hour and remains 0.647 V after the test. Further, the PPy-impregnated polyimide (PI) nanofiber mat composite membrane (PI@PPy) with an optimal thickness is fabricated with enhanced dimensional stability, of which acid swelling ratio noticeably declined by 51% in area and 25% in volume. A higher peak power density (634 mW cm −2 ) and less cell voltage reduction is also observed in the composite membrane, benefits from the trade–off between proton conductivity and PA retention ability. The results of the present study may contribute to further studies on polypyrrolone-based HT-PEMs and composite membranes.
研究领域:
材料科学
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能源科学
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产品关联
DOI
高影响因子
Journal of Energy Chemistry
·
2023
·
IF 13.1
Zhengyan Du,Zeshuo Meng,Chao Jiang,Chenxu Zhang,Yanan Cui,Yaxin Li,Chong Wang,Xiaoying Hu,Shansheng Yu,Hongwei Tian
During oxygen evolution reaction (OER), complex changes have been reported on surfaces of bimetallic Fe-Ni-based catalysts, and regulating the dynamic evolution could improve their electrocatalytic performances. Herein, a pyrrolidone-promoted reconstruction of pentlandite was investigated to uncover the correlation between the reconstructed surface and the OER performance. The theoretical calculations indicated the preferential implantation of pyrrolidone at Fe atoms, useful for regulating the electronic structures of pentlandite. The valence state of Ni increased, suggesting the promotion of the in-situ reconstruction of pentlandite via strengthening hydroxyl adsorption to generate highly active NiOOH. The electron-rich pentlandite was also found conducive to charge transfer under applied voltages. The Operando Raman and various quasi-in-situ characterizations confirmed the realization of more delocalized electronic structures of pentlandite by introducing pyrrolidone. This, in turn, promoted the accumulation of hydroxyl groups on the pentlandite surface, thereby boosting the formation of highly active NiOOH at lower OER potentials. Consequently, the adsorption energies of intermediates were optimized, conducive to enhanced OER reaction kinetics. As a proof of concept, the pentlandite decorated by pyrrolidone exhibited an overpotential as low as 265 mV at 10 mA cm −2 coupled with stable catalysis for 1000 hours at a high current density of 100 mA cm −2 . In sum, new insights into unlocking the high catalytic activity of bimetallic Fe-Ni-based catalysts were provided, promising for future synthesis of advanced catalysts.
研究领域:
材料科学
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电化学
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产品关联
DOI
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
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2024
·
IF 4.9
Chunhui Li,Shuozhen Cheng,Jinfeng Dong,Xuefeng Li
A series of block copolymers poly ( N -2-(methacryloyloxy) ethyl pyrrolidone)- b -poly (benzylmethacrylate) (PNMP 39 - b -PBzMA n ) were developed. These amphiphilic copolymers formed diversified aggregates in water, depending on the degree of polymerization n of the PBzMA segment. There presented the n -induced morphological transition from spherical micelles to vesicles via wormlike micelles. Moreover, PNMP 39 - b -PBzMA n aggregates were excellent dual function emulsifiers, showing similarity with both particles and surfactants simultaneously. The emulsification of PNMP 39 - b -PBzMA n aggregates was affected significantly by the degree of polymerization n of the PBzMA segment and oil. However, the effect of oil was more remarkable in comparison with that of n , in which the compatibility between oil and the hydrophobic PBzMA segment was critical. In general, O/W and W/O emulsions were formed for oils with poor and good compatibility to the PBzMA segment such as nonpolar alkanes and toluene, respectively. In these cases, PNMP 39 - b -PBzMA n aggregates were remained in water in the alkane/water systems, whereas they were transferred into the toluene phase according to the similarity-intermiscibility principle. For isopropyl myristate, a polar oil with the intermediate compatibility to the PBzMA segment, PNMP 39 - b -PBzMA n in water were transferred into the oil phase partially. Accordingly, emulsifiers in water and oil benefit the formation of O/W and W/O emulsions, respectively, as observed in the alkane/water and toluene/water systems. As a result, O/W and W/O emulsions were generated by PNMP 39 - b -PBzMA n with relatively small and large n , respectively. For PNMP 39 - b -PBzMA n with the intermediate n , W/O/W multiple emulsions were formed attributing to the synergistic emulsification of PNMP 39 - b -PBzMA n in water and oil.
研究领域:
材料科学
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化学工程
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产品关联
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2025
·
IF 8.2
Kaiwei Wang,Fumin Wang,Xubin Zhang,Mingshuai Sun,Yi Zhai,Yihao Wang,Hongyu Wang,Yang Qin,Hao Ruan
Nanosheet MFI zeolite with a shortened b-axis length is highly desirable for industrial applications due to the predominant mass transfer pathway provided by its larger straight channels along the b-axis. The introduction of specific additives into the precursor fluid of the zeolite can facilitate crystal anisotropic growth. However, the range of available additives is limited, and their role and underlying mechanisms remain poorly understood. Herein, the effect of three pyrrolidone compounds on the anisotropic growth of the TS-1 zeolite is unveiled within the crystallization engineering, such as 2-pyrrolidone, N-methylpyrrolidone, and N-vinyl-2-pyrrolidinone. The effects of different water content (H2O/SiO2 = 40, 100, and 160), pyrrolidone compound addition (x/SiO2 = 0.2, 0.6, 1, and 2), and seed liquid concentration on the nanosheet morphology of zeolite were studied. The TS-1 nanosheet zeolite synthesized using pyrrolidone compounds as an additive exhibits abundant high coordination titanium active sites and demonstrates excellent catalytic performance in olefin epoxidation. In this work, the crystals form a nanosheet zeolite in a nonclassical growth path. The ATS-100-1-1 sample had a thickness of 112 nm in the b-axis direction and an Lc/Lb aspect ratio of 20.08. The development of morphological engineering strategies can be extended to zeolites with other topological structures based on the intrinsic properties and interactions of additive molecules with different crystal faces.
研究领域:
材料科学
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催化化学
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF MATERIALS SCIENCE
·
2021
·Vol. 56
·期 15
·9344-9355
·
IF 4.22
Fang Dan,Yan Bin,Agarwal Seema,Xu Wenhui,Zhang Qian,He Shuijian,Hou Haoqing
The separator is an important component for energy storage devices. At present, the membranes for supercapacitors are rare, especially the ones that work with an alkaline electrolyte. Herein, a type of flexible and highly porous polymer hybrid nanofiber membrane was prepared via a facile electrospinning process and served as a separator for supercapacitor’s work with strong alkaline electrolyte. As obtained, poly[poly(2,5-benzophenone)]bibenzopyrrolone/polyimide (PBPY/PI) membrane showed good thermal stability, high mechanical strength, large electrolyte uptake (452%), and fast ion conductivity (0.68 mS/cm). Moreover, PBPY/PI membrane exhibited excellent alkali resistance. The supercapacitor assembled with PBPY/PI membrane showed much better performance than those assembled with a commercial polypropylene membrane and electrospun polyimide nanofiber membrane and was found without capacitance loss after charge/discharge at 30 A/g for 10,000 cycles at 80 °C. The PBPY/PI membrane is a good candidate with temperature resistance and alkali resistance for high-performance supercapacitors.
研究领域:
材料科学
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能源存储技术
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产品关联
DOI
高影响因子
BIOORGANIC CHEMISTRY
·
2021
·
IF 5.275
Dongjuan Si,Huijuan Luo,Xiaomeng Zhang,Kundi Yang,Hongmei Wen,Wei Li,Jian Liu
Inhibition of the interactions of the tumor suppressor protein p53 with its negative regulators MDM2 in vitro and in vivo , representing a valuable therapeutic strategy for cancer treatment. The natural product chalcone exhibited moderate inhibitory activity against MDM2, thus based on the binding mode between chalcone and MDM2, a hit unsaturated pyrrolidone scaffold was obtained through virtual screening. Several unsaturated pyrrolidone derivatives were synthesized and biological evaluated. As a result, because the three critical hydrophobic pockets of MDM2 were occupied by the substituted-phenyl linked at the pyrrolidone fragment, compound 4 h demonstrated good binding affinity with the MDM2. Additionally, compound 4 h also showed excellent antitumor activity and selectivity, and no cytotoxicity against normal cells in vitro . The further antitumor mechanism studies were indicated that compound 4 h could successfully induce the activation of p53 and corresponding downstream p21 proteins, thus successfully causing HCT116 cell cycle arrest in the G1/M phase and apoptosis. Thus, the novel unsaturated pyrrolidone p53-MDM2 inhibitors could be developed as novel antitumor agents.
研究领域:
药物化学
·
癌症生物学
·
药理学
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产品关联
DOI
PubMed
高影响因子
Journal of Macromolecular Science Part A-Pure and Applied Chemistry
·
2022
·
IF 2.216
Hao Dong,Ganhui Shi,Xianjian Wang,Xuegang Chen
A series of D-A copolymers with naphthodithiophene (NDT) as the electron-donor (D) and benzodipyrrolidone (BDPP) as the electron-acceptor (A), namely PBDPP-NDT, PBDPP-NDT-T10, PBDPP-NDT-T20, and PBDPP-NDT-T30, were synthesized by Stille coupling polymerization. Through incorporating different contents of additional thiophene units into main chains, the photophysical and electrochemical properties of the copolymers were finely regulated. Based on strong intraolecular charge transfer transition, the polymer films exhibited broad absorption bands in the range of 400–750 nm and the maxima absorption peaks of the four copolymer films were 584, 526, 437 and 566 nm, respectively. The four D-A polymers showed narrow band gaps and the electrochemical band gaps of the polymers were 1.34, 1.61, 1.64, and 1.34 eV, respectively. All of the copolymers had excellent thermal stability and the thermal decomposition temperature was above 380 °C.
研究领域:
高分子化学
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材料科学
·
有机电子学
·
物理化学
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DOI
高影响因子
DYES AND PIGMENTS
·
2024
·
IF 4.1
Xianjian Wang,Ziyuan He,Zihan Ma,Longhao Zhao,Chunhua Xie,Xuegang Chen
Constructing highly coplanar polymer backbone plays an important role in boosting the carrier mobility of organic field effect transistors (OFETs) devices. In this study, based on noncovalent conformational locks strategy, we synthesized the electron-acceptor (A) monomer via introducing 3-dodecylthiophene on strong electron-deficient planar benzodipyrrolidone and the electron-donor (D) monomers containing different numbers (0–2) of fluorine atoms at different positon. A series of novel D-A copolymers, namely PBDP-F0 , PBDP-F1 and PBDP-F2 with different backbone conformational locks through F⋯S and F⋯H–C noncovalent interactions, were obtained via Stille polycondensation . For the application in an organic field-effect transistor, all the polymers exhibited p-type charge transport characteristics and good performance with the highest hole mobilities as 0.24 cm 2 V −1 s −1 for PBDP-F0 , 0.87 cm 2 V −1 s −1 for PBDP-F1 and 1.93 cm 2 V −1 s −1 for PBDP-F2 , respectively. AFM and GIXRD investigations indicated that all polymers take predominantly edge-on orientation packing mode because of the rigid and coplanar backbone conformation and the annealing films exhibited small π-π stacking distances of 3.73, 3.71 and 3.69 Å for PBDP-F0 , PBDP-F1 and PBDP-F2 respectively. This work demonstrates that modified BDP-based D-A copolymers with conformational locks has a potential application in the high-performance semiconductor materials.
研究领域:
材料科学
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有机电子学
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半导体物理
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DOI
高影响因子
危险品化学品经营许可证（带存储）