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Water-assisted and protein-initiated fast and controlled ring-opening polymerization of proline N-carboxyanhydride

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National Science Review 2022年第8期9卷 89-99页

作者： Yali Hu Zi-You Tian Wei Xiong Dedao Wang Ruichi Zhao Yan Xie Yu-Qin Song Jun Zhu Hua Lu Beijing National Laboratory for Molecular Sciences Center for Soft Matter Science and EngineeringKey Laboratory of Polymer Chemistry and Physics of the Ministry of EducationCollege of Chemistry and Molecular EngineeringPeking University Peking-Tsinghua Center for Life Sciences Academy for Advanced Interdisciplinary StudiesPeking University Key Laboratory of Carcinogenesis and Translational Research (Ministry of Education) Department of LymphomaPeking University Cancer Hospital and Institute

The production of polypeptides via the ring-opening polymerization(ROP) of N-carboxyanhydride(NCA) is usually conducted under stringent anhydrous conditions. The ROP of proline NCA(ProNCA)for the synthesis of poly-L-proline(PLP) is particularly challenging due to the premature product precipitation as polyproline type I helices, leading to slow reactions for up to one week, poor control of the molar mass and laborious workup. Here, we report the unexpected water-assisted controlled ROP of Pro NCA, which affords well-defined PLP as polyproline II helices in 2–5 minutes and almost-quantitative yields. Experimental and theoretical studies together suggest the as-yet-unreported role of water in facilitating proton shift, which significantly lowers the energy barrier of the chain propagation. The scope of initiators can be expanded from hydrophobic amines to encompass hydrophilic amines and thiol-bearing nucleophiles, including complex biomacromolecules such as proteins. Protein-mediated ROP of ProNCA conveniently affords various protein-PLP conjugates via a grafting-from approach. PLP modification not only preserves the biological activities of the native proteins, but also enhances their resistance to extreme conditions. Moreover, PLP modification extends the elimination half-life of asparaginase(ASNase) 18-fold and mitigates the immunogenicity of wt ASNase >250-fold(ASNase is a first-line anticancer drug for lymphoma treatment). This work provides a simple solution to a long-standing problem in PLP synthesis,and offers valuable guidance for the development of water-resistant ROP of other proline-like NCAs. The facile access to PLP can greatly boost the application potential of PLP-based functional materials for engineering industry enzymes and therapeutic proteins.

关键词： proline PPII helix ring-opening polymerization N-carboxyanhydride protein-polymer conjugates

Catalytic properties of 4,5-bridged proline methano- and ethanologues in the Hajos-Parrish intramolecular aldol reaction

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Organic Chemistry Frontiers 2022年第3期9卷 649-659页

作者： Sofiane Hocine Gilles Berger K.N.Houk Stephen Hanessian aDepartment of Chemistry Universitéde MontréalStation Centre-VilleC.P.6128MontrealQCH3C 3J7Canada Microbiology Bioorganic&Macromolecular ChemistryFaculty of PharmacyUniversitéLibre de BruxellesBd du Triomphe1050 BrusselsBelgium Department of Chemistry and Biochemistry University of CaliforniaLos AngelesCA 90095-1569USA

The catalysis of the Hajos-Parrish reaction by cis-and trans-4,5-ethano-proline was explored experimentally and computationally with DFT(ωB97X-D and MN15)and DLPNO-CCSD(T).Both of the new catalysts are as active as proline or cis-and trans-4,5-methano-proline,with the trans-ethano-proline being as enantioselective as proline.A thorough theoretical analysis of the electronic factors influencing catalysis is reported.

关键词： CCSD(T) proline catalysis

Drought-induced proline is mainly synthesized in leaves and transported to roots in watermelon under water deficit

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Horticultural Plant Journal 2022年第5期8卷 615-626页

作者： Zhongyuan Wang Yongchao Yang Vivek Yadav Wei Zhao Yaping He Xian Zhang Chunhua Wei College of Horticulture State Key Laboratory of Crop Stress Biology in Arid AreasNorthwest A&F UniversityYangling 712100ShaanxiChina College of Biological and Agricultural Sciences Honghe UniversityMengzi 661100YunnanChina State Key Laboratory of Vegetable Germplasm Innovation Tianjin Kernel Agricultural Corporation LtdTianjin 300384China

proline accumulation has been shown to occur in plants in response to various environmental stresses.Although proline metabolismrelated genes have been functionally characterized,the inter-organ transport of proline in stressed plants remains unclear.In this study,free proline was detected with significant accumulations in the roots,stems,and leaves of watermelon drought-tolerant germplasm M08 and drought-susceptible line Y34 under drought stress.Expression profiling and enzyme activity measurements revealed that ClP5CS1 gene,rather than its paralog ClP5CS2,mainly contributes to the proline synthesis in leaves via the Glu pathway.Additionally,over-expression of the ClP5CS genes significantly enhanced the drought tolerance of transgenic Arabidopsis lines.Furthermore,we confirmed that proline is mainly synthesized in leaves and transported to roots in watermelon under drought stress.Transcriptome and expression analyses revealed that the genes involved in proline metabolism exhibited different expression levels.Specifically,ClP5CS1 was upregulated in leaves and roots,while ClP5CS2 was downregulated under drought stress.Also,415 and 362 differently expressed TFs were identified in roots and leaves,respectively,with the majority upregulated in the former.Ultimately,a model for proline metabolism was proposed.The findings of this study provided new insights into the biosynthesis,transport,and regulatory mechanism of drought-induced proline in plants.

关键词： Watermelon Drought stress proline Inter-organ transport

Drought Tolerance in Mung Bean is Associated with the Genotypic Divergence, Regulation of proline, Photosynthetic Pigment and Water Relation

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Phyton-International Journal of Experimental Botany 2023年第3期92卷 955-981页

作者： Mohammad Rafiqul Islam Mohd Mostofa Kamal Mohammad Faruk Hossain Jamil Hossain Mohammad Golam Azam Mst Masuma Akhter MKamrul Hasan Ibrahim Al-Ashkar Khalid FAlmutairi Ayman EL Sabagh Md Atikur Rahman Muhammad Aamir Iqbal Mohammad Sohidul Islam Agronomy Division Regional Agricultural Research StationBangladesh Agricultural Research Institute(BARI)Pabna6600Bangladesh Chief Research Scientist New Edge MicrobialsLtd.Albury2641Australia Horticulture Research Centre Regional Agricultural Research StationBangladesh Agricultural Research Institute(BARI)Pabna6600Bangladesh Pulses Research Centre BARIPabna6600Bangladesh Agronomy Division Bangladesh Wheat and Maize Research InstituteDinajpur5200Bangladesh Department of Agronomy Hajee Mohammad Danesh Science and Technology UniversityDinajpur5200Bangladesh Department of Plant Production College of Food and AgricultureKing Saud UniversityRiyadh11451Saudi Arabia Department of Agronomy Faculty of AgricultureKafrelsheikh UniversityKafrelsheikh33156Egypt Grassland and Forage Division National Institute of Animal ScienceRural Development AdministrationCheonan31000Korea Department of Agronomy Faculty of AgricultureUniversity of Poonch RawalakotRawalakot12350Pakistan Department of Genetics and Plant Breeding Faculty of AgricultureBangladesh Agricultural UniversityMymensingh2202Bangladesh

Drought is one of the critical conditions for the growth and productivity of many crops including mung bean(Vigna radiata L.Wilczek).Screening of genotypes for variations is one of the suitable strategies for evaluating crop adaptability and global food security.In this context,the study investigated the physiological and biochemical responses of four drought tolerant(BARI Mung-8,BMX-08010-2,BMX-010015,BMX-08009-7),and four drought sensitive(BARI Mung-1,BARI Mung-3,BU Mung-4,BMX-05001)mung bean genotypes under wellwatered(WW)and water deficit(WD)conditions.The WW treatment maintained sufficient soil moisture(22%±0.5%,i.e.,30%deficit of available water)by regularly supplying water.Whereas,the WD treatment was maintained throughout the growing period,and water was applied when the wilting symptom appeared.The drought tolerant(DT)genotypes BARI Mung-8,BMX-08010-2,BMX-010015,BMX-08009-7 showed a high level of proline accumulation(2.52–5.99 mg g^(−1) FW),photosynthetic pigment(total chlorophyll 2.96–3.27 mg g^(−1) FW at flowering stage,and 1.62–2.38 mg g^(−1) FW at pod developing stage),plant water relation attributes including relative water content(RWC)(82%–84%),water retention capacity(WRC)(12–14)as well as lower water saturation deficit(WSD)(19%–23%),and water uptake capacity(WUC)(2.58–2.89)under WD condition,which provided consequently higher relative seed yield.These indicate that the tolerant genotypes gained better physiobiochemical attributes and adaptability in response to drought conditions.Furthermore,the genotype BMX-08010-2 showed superiority in terms of those physio-biochemical traits,susceptibility index(SSI)and stress tolerance index(STI)to other genotypes.Based on the physiological and biochemical responses,the BMX-08010-2 was found to be a suitable genotype for sustaining yield under drought stress,and subsequently,it could be recommended for crop improvement through hybridization programs.In addition,the identified traits can be used as markers to identify tolerant genotypes for drought-prone areas

关键词： Mung bean drought proline chlorophyll water status stress tolerance

Effect of Water Stress Induced by Polyethylene Glycol on Growth, proline Accumulation in Agave americana L.

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Phyton-International Journal of Experimental Botany 2023年第2期92卷 629-643页

作者： Alfaro-Corres Arnoldo Enrique Lecona-Guzman Carlos Alberto Gutiérrez-Miceli Federico Antonio Martínez-Esteves Manuel Silverio-Gómez María del Carmen Medina-Lara María de Fátima Ruiz-Lau Nancy Laboratorio de Biotecnología vegetal Instituto Tecnológico de Tuxtla GutiérrezTuxtla Gutiérrez29050México Centro de Investigación Científica de Yucatán Unidad de Bioquímica y Biología Molecular de PlantasMérida97205México Insituto Nacional de Investigaciones Forestales Agrícolas y PecuariasHuimanguilloTabasco86400México CONACYT-Tecnológico Nacional de México/Instituto Tecnológico de Tuxtla Gutiérrez Tuxtla Gutiérrez29050México

The effect of water deficit was determined on both in vitro and soil seedling as well as in cells in suspension of Agave americana L.In order to do the establishment of cells,the formation of callus was induced;for it two auxins were evaluated:2,4-dichlorophenoxyacetic acid(2,4-D)and 4-mino-3,5,6-trichloropicolinic acid(picloram)at three concentrations(0.25,0.5 and 0.75 mg L−1)in three explants(leaf,root and meristems)cultured in MS semisolid medium.The callogenesis response was related to the type and section of the explant,as well as the regulator used,and a cell suspension was established using 0.5 mg L−1 naphthaleneacetic acid(NAA)+0.5 mg L−1 Benzylaminopurine(BAP).Seedlings were exposed to polyethyleneglycol(15%and 30%w/v)with a water potential of−0.87 and−2.67 MPa,respectively,under soil conditions.Water stress was applied through restricted irrigation.Fresh weight,root system growth,and chlorophyll concentration were some of the parameters that were affected by the effect of water deficit on A.americana L.Chlorophyll concentration values were significantly decreased by 15 at 30%PEG(19.6 SPAD units)compared to the control treatment.In in vitro plants,the highest concentration of proline was found in the roots,being the treatment with 30%polyethylene glycol where the highest concentration of this osmoregulator was obtained(62.5 mg g−1 DW).Under restricted irrigation conditions,an increase in proline concentration was observed both in the aerial part(2.2μg 100 g−1 DW)and in the root system(1.8μg 100 g−1 DW).However,the concentrations found were approximately ten times greater,less than those found under in vitro conditions.Therefore,the accumulation of proline can be considered an indicator of stress in Agave Americana L.growth in vitro.

关键词： Agave americana water deficit proline

proline Catalyzed Asymmetric Aldol Reaction between Methyl Ketones and a-Ketoesters

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Chinese Journal of Chemistry 2006年第9期24卷 1196-1199页

作者：王亚军沈宗旋李斌张雅文 Key Laboratory of Organic Synthesis of Jiangsu Province College of Chemistry and Chemical Engineering Suzhou University Suzhou Jiangsu 215006 China

Direct asymmetric aldol additions of acetone/and butanone to a-ketoesters were achieved using L-proline as a chiral catalyst. Various optically active a-hydroxyesters were obtained in the yields of 43%-93% with enantioselectivities up. to 81% e.e. The steric effect seems to be an important factor which influences the activity and the selectivity of the reaction. Acetone showed higher reactivity than butanone while the latter provided better enantioselectivity in some cases.

关键词： proline catalysis asymmetric aldol addition α-ketoester

proline-derived in situ synthesis of nitrogen-doped porous carbon nanosheets with encaged Fe203@Fe3C nanoparticles for lithium-ion battery anodes

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Nano Research 2017年第9期10卷 3164-3177页

作者： Jingfei Zhang Lijuan Qi Xiaoshu Zhu Xiaohong Yan Yufeng Jia Lin Xu Dongmei Sun Yawen Tang Jiangsu Key Laboratory of New Power Batteries _llangsu Collaborative Innovation Center of Biomedical FunctionaI Materials Analysisand Testing Center School of Chemistry and Materials Science Nanjing Normal University Nanjing 210023 China

The homogeneous incorporation of heteroatoms into two-dimensional C nanostructures, which leads to an increased chemical reactivity and electrical conductivity as well as enhanced synergistic catalysis as a conductive matrix to disperse and encapsulate active nanocatalysts, is highly attractive and quite challenging. In this study, by using the natural and cheap hydrotropic amino acid proline—which has remarkably high solubility in water and a desirable N content of ~12.2 wt.%—as a C precursor pyrolyzed in the presence of a cubic KCl template, we developed a facile protocol for the large-scale production of N-doped C nanosheets with a hierarchically porous structure in a homogeneous dispersion. With concomitantly encapsulated and evenly spread Fe2O3 nanoparticles surrounded by two protective ultrathin layers of inner Fe3C and outer onion-like C, the resulting N-doped graphitic C nanosheet hybrids (Fe2O3@Fe3C-NGCNs) exhibited a very high Li-storage capacity and excellent rate capability with a reliable and prolonged cycle life. A reversible capacity as high as 857 mAh•g–1 at a current density of 100 mA•g–1 was observed even after 100 cycles. The capacity retention at a current density 10 times higher—1,000 mA•g–1—reached 680 mAh•g–1, which is 79% of that at 100 mA•g–1, indicating that the hybrids are promising as anodes for advanced Li-ion batteries. The results highlight the importance of the heteroatomic dopant modification of the NGCNs host with tailored electronic and crystalline structures for competitive Li-storage features.

关键词： proline N-doped C nanosheet porous encaged Fe 2 O 3 @Fe 3 C Li-ion battery

Phytotoxicity of cadmium on protein, proline and antioxidant enzyme activities in growing Arachis hypogaea L. seedlings

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Journal of Environmental Sciences 2008年第2期20卷 199-206页

作者： N Dinakar P C Nagajyothi S Suresh Y Udaykiran T Damodharam Department of Environmental Sciences Sri Venkateswara UniversityTirupatiAndhra Pradesh-517 502India.

Phytotoxicity of cadmium on growing Arachis hypogaea L. seedlings was studied. Seeds were exposed to 25, 50, and 100 μmol/L CdCl2 concentrations, for a period of 10, 15, 20 and 25 d. The extent of damage to chlorophyll, protein, proline, nitrate and nitrite reductase, antioxidant enzyme activity in leaves and roots were evaluated after 10 d of cadmium stress. The higher concentration of cadmium （100 μmol/L） resulted （leaves and roots） total chlorophyll 91.01%, protein 79.51%, 83.61%, nitrate reductase 79.39%, 80.72% and nitrite reductase 77.07%, 75.88% activity decreased with increase in cadmium concentrations and exposure periods. Cadmium caused significant changes in the activity of antioxidative enzymes. Contrastingly Cd treated plant tissues showed an increase in proline 159.87%, 239.6%, gluthion reductase （GR） 337.72%, 306.14%, superoxide disumutase （SOD） 688.56%, 381.72%, ascorbate peroxidase （APX） 226.47%, 252.14%, peroxidase （POD） 72.19%, 60.29% and catalase （CAT） 228.96%, 214.74% as compared to control. Cadmium stress caused a significant increase in the rate of SOD activity in leaves and roots of plant species. Results show the crop A. hypogaea is highly sensitive even at very low cadmium concentrations.

关键词： toxicological effects cadmium protein proline antioxidant enzymes

proline Catalyzed Asymmetric Aldol Reaction between Methyl Ketones and 1-Aryl-2,2,2-trifluoroethanones

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Chinese Journal of Chemistry 2005年第5期23卷 584-588页

作者：邱丽华沈宗旋石常青刘艳华张雅文 KeyLaboratoryofOrganicSynthesisofJiangsuProvince CollegeofChemistryandChemicalEngineeringSuzhouUniversitySuzhouJiangsu215006China

Direct asymmetric aldol addition of methyl ketones to 2,2,2‐trifluoro‐1‐phenylethanone and its ring‐substituted derivatives was achieved using L ‐proline as a chiral promoter. Various optically active β‐trifluoromethyl‐β‐hydroxy ketones were obtained in almost quantitative yields with moderate enantioselectivities up to 64 % ee.

关键词： proline aldol addition 1‐aryl‐2,2,2‐trifluoroethanone