检索结果-南通市图书馆

Science China Chemistry 2017年第8期60卷 1115-1129页

作者： Xian Chen Tianmin Wu Zhe-Ning Chen Tan Jin Wei Zhuang Yisong Zheng State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of Matte~ Chinese Academy of Sciences Fuzhou 350002. China

We review in this article our recent simulation works on modeling peptide T-jump and thermal unfolding Fourier transform infrared spectroscopy(FTIR) and two-dimensional infrared(2DIR) spectra. The theoretical and computational techniques used,including Markov state model(MSM), integrated tempering sampling(ITS) and nonlinear exciton propagation(NEP), are first briefly introduced. The protocols for simulating the thermal unfolding as well as T-jump unfolding are then summarized in details. The simulated spectral features, such as the intensity and ellipticity, are demonstrated to agree well with the experimental observations.

关键词： polypeptides amide vibration nonlinear response MSMs T-jump implicit solvent model ITS 2DIR folding landscape

Synthesis,Characterization and Phase Behaviors of polypeptides Bearing Biphenyl Mesogens and Oligo-Ethylene-Glycol Tails

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Polymer Science 2015年第8期33卷 1150-1161页

作者： Qiu-lin Yuan Wen-jun Liu Yong Deng Ying Ling 唐浩宇 Key Laboratory of Polymeric Materials and Application Technology of Hunan Province Key Laboratory of Advanced Functional Polymer Materials of Colleges and Universities of Hunan ProvinceCollege of ChemistryXiangtan University

A series ofpolypeptides bearing biphenyl mesogenic side-chains and oligo-ethylene-glycol （OEG） tails （PPLGn-g- BPOEGm, n = 26 and 63, m = 2, 3, and 7） has been synthesized via a 1,3-dipolar cycloaddition with quantitative grafting density. FTIR results revealed that the polypeptides adopted highly stable a-helix in the temperature range of 25-200 ℃. DSC, POM and WAXS analysis revealed that PPLGn-g-BPOEGm （m ≤ 3） samples with short OEG tail length showed two main phase transitions including crystal to liquid crystalline （smectie C, SmC） phase transition and the melting transition of crystalline E-phase, while PPLG,-g-BPOEG7 with longer OEG tail length （m = 7） exhibited the melting transitions without the formation of liquid crystalline phase.

关键词： Liquid-crystalline polymers polypeptides Click chemistry Smectic phases.

Regulation of the cellular uptake of nanopartides by the orientation of helical polypeptides

在线全文

学校读者我要写书评

暂无评论

Nano Research 2019年第4期12卷 889-896页

作者： Chong Zhang Jianhua Lu Falin Tian Lindong Li Yingqin Hou Yaoyi Wang Lingdong Sun Xinghua Shi Hua Lu Beijing National Laboratory for Molecular Sciences College of Chemistry and Molecular Engineering Peking University Beijing 100871 China Center for Soft Matter Science and Engineering Key Laboratory of Polymer Chemistry and Physics of Ministry of Education Peking University Beijing 100871 China CAS Key Laboratory of Nanosystem and Hierarchical Fabrication CAS Center for Excellence in Nanoscience National Center for Nanoscience and Technology Beijing 100190 China State Key Laboratory of Rare Earth Materials Chemistry and Applications PKU-HKU Joint Laboratory in Rare Earth Materials and Bioinorganic Chemistry Peking University Beijing 100871 China

Controlling the cellular interactio n and internal izatio n of polymer-modified nan oparticles (NPs) is of central importa nee to the developme nt of promisi ng nano medici nes. Here, we describe the use of synthetic polypeptides for NP surface coati ng and regulati on of their cellular uptake behaviors by simply switching the conformation and anchoring orientation. Our results show that gold NPs (AuNPs) coated with a helical poly(Y-(2-(2-(2-methoxyethoxy)ethoxy)ethoxy)esteryl「glutamate)(L-P(EG3Glu)5o) from the C-terminus ((L-C)-AuNPs) exhibit greater zeta potential and more cellular uptake (2.0-5.5 fold higher) than those coated with the same polypeptide but anchored from the N-terminus ((L-N)-AuNPs), or from both the C- and N-terminus at a 1/1 molar ratio ((L-C/L-N)-AuNPs). A similar orientation-regulated cellular internalization pattern is observed in D-P(EG3Glu)50 but not the unstructured DL-P(EG3Glu)5o-rnodified AuNPs, suggesting an important and universal role of the helix-derived macrodipole in cellular uptake. Moreover, this orientation-governed internalization is successfully reproduced in P(EG3Glu)50-coated gold nano rods (AuNRs), and applied to the desig n of doxorubici reloaded polypeptide micelles. Simulation study offers time-resolved in sights regarding the NP-membrane in teracti ons and membrane remodeling. Thus, our study provides a delicate way of regulating the surface chemistry of NPs and the subsequent NP-cell interactions. Moreover, the results highlight the uniqueness of polypeptides in NP surface engineering, and urge a more careful consideration on the polymer orientation effect.

关键词： helix orientation polypeptides cellular uptake gold nanoparticles

Achyranthes bidentata polypeptides prevent apoptosis by inhibiting the glutamate current in cultured hippocampal neurons

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Neural Regeneration Research 2020年第6期15卷 1086-1093页

作者： Rong-Lu Pan Wen-Qing Hu Jie Pan Li Huang Cheng-Cheng Luan Hong-Mei Shen Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education and Institute of Nautical Medicine Co-Innovation Center of NeuroregenerationNantong UniversityNantongJiangsu ProvinceChina Department of Neurobiology Physiology and BehaviorCollege of Biological ScienceDavisCAUSA Affiliated Mental Health Center of Nantong University Nantong Brain HospitalNantongJiangsu ProvinceChina

Glutamate-induced excitotoxicity plays a critical role in the neurological impairment caused by middle cerebral artery *** bidentata polypeptides have been shown to protect against neurological functional damage caused by middle cerebral artery occlusion,but the underlying neuroprotective mechanisms and the relationship to glutamate-induced excitotoxicity remain ***,in the current study,we investigated the protective effects of Achyranthes bidentata polypeptides against glutamate-induced excitotoxicity in cultured hippocampal *** neurons were treated with Mg^2+-free extracellular solution containing glutamate(300μM)for 3 hours as a model of glutamate-mediated excitotoxicity(glutamate group).In the normal group,hippocampal neurons were incubated in Mg^2+-free extracellular *** the Achyranthes bidentata polypeptide group,hippocampal neurons were incubated in Mg^2+-free extracellular solution containing glutamate(300μM)and Achyranthes bidentata polypeptide at different *** 24 hours after exposure to the agents,3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay and Hoechst 33258 staining were used to assess neuronal viability and nuclear m'orphology,***-3 expression and activity were evaluated using western blot assay and colorimetric enzymatic assay,*** various time points after glutamate treatment,reactive oxygen species in cells were detected by H2 DCF-DA,and mitochondrial membrane potential was detected by rhodamine 123 *** examine the effect of Achyranthes bidentata polypeptides on glutamate receptors,electrophysiological recording was used to measure the glutamate-induced inward current in cultured hippocampal *** bidentata polypeptide decreased the percentage of apoptotic cells and reduced the changes in caspase-3 expression and activity induced by *** addition,Achyranthes bidentata polypeptide attenuated the amplitud

关键词： Achyranthes bidentata polypeptides apoptosis caspase-3 excitotoxicity glutamate receptors mitochondrial dysfunction mitochondrial membrane potential neuroprotection reactive oxygen species staurosporine

Selective protection of glycinebetaine on extrinsic polypeptides of PS Ⅱ particles

在线全文

学校读者我要写书评

暂无评论

Chinese Science Bulletin 1997年第20期42卷 1744-1748页

作者： HOU Caixia, XU Chunhe, TANG Zhangcheng and SHEN YunkangShanghai Institute of Plant Physiology, Chinese Academy of Sciences, Shanghai 200032, China Shanghai Institute of Plant Physiology Chinese Academy of Sciences Shanghai China

PHOTOSYSTEM Ⅱ（PS Ⅱ） particles capable of O2 evolution contain D1, D2 transmembrane pro-teins, and three extrinsic polypeptides which are exposed to the outer aqueous phase with ap-parent molecular masses of 33, 23, 18 kD. The three proteins can be partially or totally re-moved by treating the PS Ⅱ membranes with high concentrations of salt or other methods,

关键词： glycinebetaine extrinsic polypeptides trichloroacetate NaCI.

Mechanism of selective stabilization of extrinsic polypeptides in PSII particles by glycinebetaine

在线全文

学校读者我要写书评

暂无评论

Science China(Life Sciences) 1998年第3期41卷 278-285页

作者：侯彩霞於新建李荣汤章城沈允钢徐春和 Shanghai Institute of Plant Physiology Chinese Academy of Sciences 200032 Shanghai China

The effect of glycinebetaine in selectively stabilizing the PSII extrinsic polypeptides was studied with PSII particles treated with different methods. It was shown that glycinebetaine markedly stabilized the PSII extrinsic polypeptides when the particles were treated with 0.8 mol/L Tris (pH8.0) or high concentrations of NaCl. The stabilizing effect was less pronounced when the PSII particles were treated by heat shock or trichloroacetate (TCA). The capability of halogenated acetates to release extrinsic polypeptides in PSII particles was found to follow the order of decreasing molecular hydrophobicities: trichloroacetate (TCA)> dichloroacetate (DCA)> monoiodoacetate (MIA)>monobromoacetate (MBA)>monochloroacetate (MCA). All these results imply that glycinebetaine is effective in stabilizing biopolymer structure against the action of electrolytes, while it is ineffective in protecting extrinsic polypeptides in PSII particles from dissociation induced by halogenated acetates or heat treatments which disturbed the hydrophobic interactions within the polypeptides.

关键词： extrinsic polypeptides glycinebetaine halogenated acetate heat PSII particles Tris.

Force-Regulated Adhesion and Activation Study of Integrin Targeting polypeptides

在线全文

学校读者我要写书评

暂无评论

医用生物力学 2019年第A1期34卷 155-155页

作者： Ke Ding Zhengjiao Cao Quan Long Ting Xiong Botao Xiao School of Biology and Biological Engineering South China University of Technology

Integrins are heterodimeric cell surface receptors that bind to ligands on another cell,*** adhesion molecule 1(ICAM-1),or the extracellular *** play an important role in immune system,and they participate in inflammation,thrombosis,and proliferation,migration and apoptosis of tumor *** mediate adhesion and transduce signals across the membrane usually under the influence of forces.A recent study has shown that integrins bind and activate transforming growth factorβisoform(TGF-β)which is involved in tumor suppression and growth,and blocking the binding of TGF-βto integrin can inhibit tumor ***(arginine-glycine-aspartate)small peptide,which competitively inhibits ligand binding to integrins,has been approved as an injectable ***,when the RGD is used to block cancer-related extracellular signaling pathways,it will also cause activation of integrins for a period,and stimulate the transduction of intracellular signals ***,it is necessary to explore for new drugs that can selectively control conformational state of integrins without activating or blocking all of *** this study,we selected two small peptides,KQAGDV and RTDLDSLRT,that combined with integrins and do not contain an RGD *** non-RGD polypeptide RTDLDSLRT has been reported to have a binding site with integrins and the binding affinity is on nanomolar *** the motif of the fibrinogen y chain C-terminal KQAGDV,it can adhere to the head of the *** micropipette aspiration technique and electron microscopy techniques were used to study the adhesion and activation of integrins by peptides,*** aspiration technique was used to investigate the adhesion frequency of peptide and integrin on Jurkat *** pressure system was used to supply a controllable negative pression to the microtube,and two micropipettes were used to absorb red blood cells and Jurkat cells,*** red blood cells were coated

关键词： Force-Regulated Adhesion Activation Study Integrin Targeting polypeptides

Modulation of polymerization rate of N-carboxyanhydrides in a biphasic system

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2024年第1期35卷 326-331页

作者： Guonan Ji Xuetao Zheng Xiangdie Hou Xiao Sun Shijie Wang Xiaohong Li Jianjun Cheng Ziyuan Song Institute of Functional Nano&Soft Materials(FUNSOM) Jiangsu Key Laboratory for Carbon-Based Functional Materials and DevicesSoochow UniversitySuzhou 215123China Research Center for Industries of the Future Westlake UniversityHangzhou 310030China School of Engineering Westlake UniversityHangzhou 310030China The Key Lab of Health Chemistry and Molecular Diagnosis of Suzhou College of ChemistryChemical Engineering and Materials ScienceSoochow UniversitySuzhou 215123China

The recent advances in accelerated polymerization of N-carboxyanhydrides (NCAs) offer an effective strategy to simplify the preparation of polypeptide materials. However, the fine-tuning of polymerization kinetics, which is critical to differentiate the main polymerization and the side reactions, remains largely unexplored. Herein we report the modulation of polymerization rate of NCA in a water/oil biphasic system. By altering the aqueous pH, the initial location of the initiators, and the pK_(a) of initiating amines, we observed the change in polymerization time from several minutes to a few hours. Due to the high interfacial activity and low pKa value, controlled polymerization was observed from multi-amine initiators even if they were initially located in the aqueous phase. This work not only improves our understanding on the biphasic polymerization mechanism, but also facilitates preparation of versatile polypeptide materials.

关键词： N-Carboxyanhydrides polypeptides Biphasic system Cooperative covalent polymerization Polymerization kinetics

Clickable,Oxidation-Responsive and Enzyme-Degradable Polypeptide:Synthesis,Characterization and Side Chain Modification

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Polymer Science 2022年第11期40卷 1360-1368页

作者： Yan-Zhi Lu An-Qi Gu Tian-Lun Shen Ji-Hong Sun Jun Ling Ministry of Education Key Laboratory of Macromolecular Synthesis and Functionalization Department of Polymer Science and EngineeringZhejiang UniversityHangzhou310027China Department of Radiology Sir Run Run Shaw HospitalSchool of MedicineZhejiang UniversityHangzhou310016China

Modifications at polypeptide side chains have been found to affect conformational and properties,which is a vital strategy to prepare functional *** contribution describes the synthesis of homo and co-polypeptides containing unsaturated bonds and thioether moieties,poly(S-allylcysteine)(PAC).The pendant vinyl groups provide an active binding site which are able to be further modified with cysteine by thiol-ene click *** sulfoxide from thioether oxidation bestows the polypeptide water solubility and enzymatic catalytic *** selfassembly micelles of PEG-b-PAC are ruptured along with oxidation to release the Nile red ***,poly(S-allyl-cysteine sulfoxide),***,is the oxidation product of PAC which undergoes side chain cleavage catalyzed by alliinase *** polypeptides are biocompatible as confirmed by cell viability assays and may find applications in drug delivery,biosensing and nanoreactor.

关键词： polypeptides Ring-opening polymerization Stimuli-responsive polymers N-carboxy anhydrides N-phenoxycarbonylα-amino acids

Thermo-induced physically crosslinked polypeptide-based block copolymer hydrogels for biomedical applications

在线全文

学校读者我要写书评

暂无评论

Regenerative Biomaterials 2023年第1期10卷 933-956页

作者： Dan Zhao Yan Rong Dong Li Chaoliang He Xuesi Chen CAS Key Laboratory of Polymer Ecomaterials Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China College of Applied Chemistry and Engineering University of Science and Technology of ChinaHefei 230026China

Stimuli-responsive synthetic polypeptide-containing block copolymers have received considerable attention in recent ***,unique thermo-induced sol-gel phase transitions were observed for elaborately-designed amphiphilic diblock copolypeptides and a range of poly(ethylene glycol)(PEG)-polypeptide block *** thermo-induced gelation mechanisms involve the evolution of secondary conformation,enhanced intramolecular interactions,as well as reduced hydration and increased chain entanglement of PEG *** physical parameters,including polymer concentrations,sol-gel transition temperatures and storage moduli,were *** polypeptide hydrogels exhibited good biocompatibility in vitro and in vivo,and displayed biodegradation periods ranging from 1 to 5 *** unique thermo-induced sol-gel phase transitions offer the feasibility of minimal-invasive injection of the precursor aqueous solutions into body,followed by in situ hydrogel formation driven by physiological *** advantages make polypeptide hydrogels interesting candidates for diverse biomedical applications,especially as injectable scaffolds for 3D cell culture and tissue regeneration as well as depots for local drug *** review focuses on recent advances in the design and preparation of injectable,thermo-induced physically crosslinked polypeptide *** influence of composition,secondary structure and chirality of polypeptide segments on the physical properties and biodegradation of the hydrogels are ***,the studies on biomedical applications of the hydrogels are intensively ***,the major challenges in the further development of polypeptide hydrogels for practical applications are proposed.

关键词： injectable hydrogels polypeptides stimuli responsive secondary conformation tissue engineering immunotherapy