Bicyclic peptides,a class of polypeptides with two loops within their structure,have emerged as powerful tools in the development of new peptide drugs.They have the potential to bind to challenged drug targets,with an...Bicyclic peptides,a class of polypeptides with two loops within their structure,have emerged as powerful tools in the development of new peptide drugs.They have the potential to bind to challenged drug targets,with antibody-like affinity and selectivity.Meanwhile,bicyclic peptides possess small molecule-like access to chemical synthesis,which is conducive to large-scale synthesis and screening.In the last five years,bicyclic peptide technology has been increasingly developed,and researchers have carried out a variety of studies to elucidate the potential functions of bicyclic peptides.With the continuous development of synthetic methods and the advances of new technology to build bicyclic peptide libraries,bicyclic peptides are now becoming widely used in the development of new drugs for various diseases.This perspective provides an overview of the structure types,synthesis and applications of bicyclic peptides in current drug development,and our own views on future challenges of bicyclic peptides.展开更多
From the ethanol extract of the roots of Brachystemma calycinum D. Don, a Chinese folk herb, four new minor cyclic peptides namely brachystemin A, B, C and D (1 - 4) have been isolated. Their structures were establish...From the ethanol extract of the roots of Brachystemma calycinum D. Don, a Chinese folk herb, four new minor cyclic peptides namely brachystemin A, B, C and D (1 - 4) have been isolated. Their structures were established as cyclo (Pro(1)-Phe-Leu-Ala(1)-Thr-Pro(2)-Ala(2)-Gly) (1), cyclo (Pro(1)-Ala-Phe-Trp-Asp-Pro(2)-Leu-Gly) (2), cyclo (Pro(1)-Ile-Gly-Pro(2)-Val-Ala(1)-Ala(2)-Tyr) (3) and cyclo ( Pro-OMet-Trp-Ile-Gly-Ala-Leu-Asp) (4) respectively by means of extensive spectral methods.展开更多
New cyclic peptides 1 and 2 were isolated from the endophytic fungus #2221 fromCastaniopsis fissa on the south China sea coast. By 2D NMR methods and chiral HPLC technique,their structures were elucidated as cyclo (L-...New cyclic peptides 1 and 2 were isolated from the endophytic fungus #2221 fromCastaniopsis fissa on the south China sea coast. By 2D NMR methods and chiral HPLC technique,their structures were elucidated as cyclo (L-Val-L-Leu-L-Val-L-Leu) and cyclo(L-Leu-L-Ala-L-Leu-L-Ala), respectively.展开更多
Chromatographic separation of the marine-derived bacterium Bacillus licheniformis resulted in the isolation of two new cyclic lipopeptides named ai-Cl6 surfactin （1） and ai-Cl4 surfactin （2）, together with iso-Cm5...Chromatographic separation of the marine-derived bacterium Bacillus licheniformis resulted in the isolation of two new cyclic lipopeptides named ai-Cl6 surfactin （1） and ai-Cl4 surfactin （2）, together with iso-Cm5 surfactin and iso-Cl6 surfactin. The structures of the new cyclic lipopeptides were determined through extensive spectroscopic analysis. The sequences of the amino acids in cyclic nucleus were established by the ESI-MS/MS fragmentation, which provided an efficient method to detect lipopeptides from bacterium extracts without senaration展开更多
Heterocycle-braced cyclic peptides have demonstrated enhanced metabolic stability,increased potency and selectivity.Here,we present a rapid synthesis method for constructing Trp(C7)-alkene(E)-crosslinked cyclic peptid...Heterocycle-braced cyclic peptides have demonstrated enhanced metabolic stability,increased potency and selectivity.Here,we present a rapid synthesis method for constructing Trp(C7)-alkene(E)-crosslinked cyclic peptides with potent anti-proliferative activities against cancer cells,through C-H alkenylation and macrolactamization.This report addresses critical challenges associated with the installation and removal of the directing group N-Piv,configuration selectivity of the olefin,and intramolecular cyclization.No-tably,this method exhibits mild reaction conditions,traceless removal of the directing group,and high configuration selectivity.展开更多
We report here the synthesis of cyclic peptides using benzotriazolyloxy-bis(pyrrolidino)-carbonium hexafluoro- phosphate(BBC)as a coupling reagent with high yield and speed even in low concentration compared with the ...We report here the synthesis of cyclic peptides using benzotriazolyloxy-bis(pyrrolidino)-carbonium hexafluoro- phosphate(BBC)as a coupling reagent with high yield and speed even in low concentration compared with the other usual coupling reagents.展开更多
This paper reports the determination of stability constants for complexes of Cd(Ⅱ)with Gly, Ala,Val,Asp,Gly—Asp,Asp Gly,Gly—Gly and Gly—Gly—Gly using both micro—pH—metric titra- tions and the application of con...This paper reports the determination of stability constants for complexes of Cd(Ⅱ)with Gly, Ala,Val,Asp,Gly—Asp,Asp Gly,Gly—Gly and Gly—Gly—Gly using both micro—pH—metric titra- tions and the application of convolution—deconvolution cyclic voltammetry at 25℃ and I=0.10 mol· dm^(-3)(KNO_3).Stability constants were calculated from pH—metric data using the SUPERQUAD com- puter program and cyclic voltammograms were collected,stored and manipulated using the EG and G CONDECON 300 software.A considerably larger ligand:metal ratio(e,g.50:1)was possible using voltammetry.Evaluation of results from the two techniques suggests that stability constants for the species[CdL_2]and[CdL_3]are reliable when calculated fromvoltammetry while those for[CdL]are more reliable when determined by pH-metric titration.展开更多
From Psammosilene tunicoides W. C. Wu et C. Y Wu, two cyclic octapeptides (namedpsammosilenins A and B) were isolated. Their structures were determined as cyclo(-Pro1-phe1-Pro2-Phe2-Phe3-Ala-Pro3-Leu-) and cyclo(-Pro...From Psammosilene tunicoides W. C. Wu et C. Y Wu, two cyclic octapeptides (namedpsammosilenins A and B) were isolated. Their structures were determined as cyclo(-Pro1-phe1-Pro2-Phe2-Phe3-Ala-Pro3-Leu-) and cyclo(-Pro1-Gly-Phe1-Val-Pro2-Phe2-Thr-Ile) by spectroscopicmethods.展开更多
The interaction between HIV-1 DNA and five cyclic peptides （CP1-CP5） was investigated using electrospray ionization mass spectrometry （ESI-MS）. It revealed that CP1 [c（Ala-Tyr-Leu-Ala-Gly）] and CP4 [c（Pro-D-Tyr...The interaction between HIV-1 DNA and five cyclic peptides （CP1-CP5） was investigated using electrospray ionization mass spectrometry （ESI-MS）. It revealed that CP1 [c（Ala-Tyr-Leu-Ala-Gly）] and CP4 [c（Pro-D-Tyr-Leu-D-Ala-Gly）] have the higher binding affinity with the duplex DNA among the five cyclic peptides.展开更多
Protein-protein interactions(PPIs) are recognized as attractive therapeutic targets. However targeting PPIs especially intracellular ones has been proven extremely difficult for conventional drug-like small molecules,...Protein-protein interactions(PPIs) are recognized as attractive therapeutic targets. However targeting PPIs especially intracellular ones has been proven extremely difficult for conventional drug-like small molecules, and biological drugs such as monoclonal antibodies have difficulty in reaching intracellular targets. Macrocyclic peptides are promising candidates of PPI regulators for their potential in combining high potency and biological stability together. Cell permeability of macrocyclic peptides may also be achieved by structural modifications or conjugation to a cell-penetrating sequence. Significant progress has been made in this research area in recent years. Important technology progress and recent examples of macrocyclic peptide PPI modulators are reviewed.展开更多
Objective:To find potential peptide inhibitors against the NS2B/NS3 protease of DENV which in turn,can inhibit the viral replication inside host cell.Methods:Cyclic peptides were designed having combination of positiv...Objective:To find potential peptide inhibitors against the NS2B/NS3 protease of DENV which in turn,can inhibit the viral replication inside host cell.Methods:Cyclic peptides were designed having combination of positively charged amino acids using ChemSketch software and were converted to 3D structures.DENV NS3 protein structure was retrieved from Protein Data Bank(PDB)using PDB Id:2FOM.DENV NS3 and cylic peptides were docked using MOE software after structural optimization.Results:Through molecular docking it was revealed that most of the peptides bound deeply in the binding pocket of DENV NS2B/NS3 protease an had interactions with catalytic triad.Peptide 2 successfully blocked the catalytic triad of NS2B/NS3 protease.Peptide 1,,4 and 6 also had potential interactions with active residues of the NS2B/NS3 protease while all other peptides were in close contact with the active sites of NS2B/NS3 protease thus,these peptides can serve as a potential drug candidate to stop viral replication.Conclusions:Thus.it can be concluded from the study that these peptides could serve as important inhibitors to inhibit the viral replication and need further in-vitro investigations to confirm their efficacy.展开更多
The Antarctic fungus Cadophora malorum produces previously undescribed cyclic heptapeptides(cadophorin A and B)containing an anthranilic acid residue.The planar structure of these peptides was determined by high-resol...The Antarctic fungus Cadophora malorum produces previously undescribed cyclic heptapeptides(cadophorin A and B)containing an anthranilic acid residue.The planar structure of these peptides was determined by high-resolution mass spectrometry combined with extensive 1D and 2D NMR spectroscopy.The absolute configuration of the amino acids was determined by Marfey’s method,with HPLC analysis of FDVA(Nα-(2,4-dinitro-5-fluorphenyl)-l-valinamide)derivatives making use of a PFP column.Remarkably,cadophorin 2 possesses both the uncommon d-Ile and d-allo-Ile in its structure.The peptides have metal binding properties as shown by LCMS with post column addition of metal salt solutions.These results were supported by DFT calculations.展开更多
In biological controls using <em>Bacillus</em> spp., cyclic lipopeptides play a role as elicitors to induce disease resistance on various host plants. However, it is still unclear the specificity between c...In biological controls using <em>Bacillus</em> spp., cyclic lipopeptides play a role as elicitors to induce disease resistance on various host plants. However, it is still unclear the specificity between cyclic lipopeptides and host plants to induce disease resistance. In this study, we aimed to clarify the specificity to induce disease resistance among cyclic lipopeptides on various host plants. Our data clearly showed both cyclic lipopeptides conferred disease suppression on most of host plants, but at different range of cyclic lipopeptide concentration. Our findings contribute to understanding the complex on the specificity of cyclic lipopeptide derived induced disease resistance.展开更多
P-113 is a fragment of natural occurring peptide Histatin 5 found in human saliva. This peptide exhibited broad spectrum of antibacterial and antifungal biological activities. In this study, bifunctional P-113 peptide...P-113 is a fragment of natural occurring peptide Histatin 5 found in human saliva. This peptide exhibited broad spectrum of antibacterial and antifungal biological activities. In this study, bifunctional P-113 peptides 2–5 were designed as Sortase A substrates and synthesized by solid support peptide synthesis,where the N-terminus were equipped with glycine and its analogues, and C-terminus were extended with LPETGGS, respectively. Under Sortase A catalyzed condition, head to tail cyclization products 7–10were afforded in yields from 76% to 93%. The conformation insights of linear peptides 2–5 and cyclic analogues 7–10 in aqueous buffers and in trifluroethanol（TFE） analyzed by circular dichroism（CD）suggested that a-helix structures were produced progressively in hydrophobic environment independent of the cyclization, which displayed the similar behavior as parent peptide P-113.展开更多
Signaling peptides are known for their prominent roles in plant growth, development, and environmental adaptation(Zhang et al., 2025). However, their extremely low natural abundance and highly dynamic expression patte...Signaling peptides are known for their prominent roles in plant growth, development, and environmental adaptation(Zhang et al., 2025). However, their extremely low natural abundance and highly dynamic expression patterns pose significant technical challenges to extract sufficient amounts with good purity for biological studies and practical applications.Consequently, chemical synthesis and microbial systems offer attractive alternatives to obtain potent peptides at higher quantities and purity. Incorporating modifications or substitutions, chemically synthetic approaches enable the creation of more effective engineered peptides such as agonists,antagonists, chemically modified peptides, or peptide-like molecules with novel functions compared to native peptides.展开更多
Among various architectures of polymers,end-group-free rings have attracted growing interests due to their distinct physicochemical performances over the linear counterparts which are exemplified by reduced hydrodynam...Among various architectures of polymers,end-group-free rings have attracted growing interests due to their distinct physicochemical performances over the linear counterparts which are exemplified by reduced hydrodynamic size and slower degradation.It is key to develop facile methods to large-scale synthesis of polymer rings with tunable compositions and microstructures.Recent progresses in large-scale synthesis of polymer rings against single-chain dynamic nanoparticles,and the example applications in synchronous enhancing toughness and strength of polymer nanocomposites are summarized.Once there is the breakthrough in rational design and effective large-scale synthesis of polymer rings and their functional derivatives,a family of cyclic functional hybrids would be available,thus providing a new paradigm in developing polymer science and engineering.展开更多
In contrast to cyclic polymers with ring-like backbones,side-chain cyclization is another intriguing structural feature that has not been extensively studied.In this study,a library of orthogonally protected monomers ...In contrast to cyclic polymers with ring-like backbones,side-chain cyclization is another intriguing structural feature that has not been extensively studied.In this study,a library of orthogonally protected monomers featuring monocyclic,dicyclic,or tricyclic pendant motifs was designed and prepared based on malic acid derivatives.Polyesters with precise chemical structures and uniform chain lengths were prepared modularly through iterative growth.Meticulous control over the chemical details allows for a close investigation of the topological effects on the polymer properties.Compared to their linear side chain counterparts,the presence of cyclic pendant groups has a significant impact on chain conformation,leading to a reduction in hydrodynamic volume and an enhancement in the glass transition temperature.These results underscore the potential of tailoring polymer properties through rational engineering of side chain topology.展开更多
Drilling and blasting tunneling is a cyclic process in which tunnel rock undergoes repeated blast loading,affecting its dynamic characteristics,energy evolution,and damage progression.To explore the dynamic mechanical...Drilling and blasting tunneling is a cyclic process in which tunnel rock undergoes repeated blast loading,affecting its dynamic characteristics,energy evolution,and damage progression.To explore the dynamic mechanical properties and damage mechanisms of carbonaceous slate under cyclic impact loads of varying intensities,cyclic dynamic tests are conducted using a triaxial split Hopkinson pressure bar.This study analyzes the stress-strain relationship,energy damage evolution,and macro-to-micro failure characteristics.The results show that peak stress and strain are significantly influenced by impact intensity and the number of impacts.The initial dynamic stress is positively correlated with the impact intensity,but with more impact,the dynamic stress decreases while the peak strain increases.Energy evolution follows a pattern of"slow growthfluctuating growthrapid growth,"with the crack initiation stress and its proportion decreasing.CT and SEM analyses reveal that as the impact intensity increases,failure becomes more chaotic,the fracture volume increases,and the fracture mode shifts from interlayer and intergranular to through-layer and trans-granular fractures.These findings provide an experimental basis for soft rock tunnel stability analysis.展开更多
Fluorescent probes,with their superior optical properties and labeling versatility,have greatly advanced the visualization of intracellular molecules and subcellular structures.However,poor cytoplasmic delivery,caused...Fluorescent probes,with their superior optical properties and labeling versatility,have greatly advanced the visualization of intracellular molecules and subcellular structures.However,poor cytoplasmic delivery,caused by charge,size,or targeting groups,limits the effective use of many fluorescent probes in live cells.Recently,cell-penetrating peptides(CPPs)have emerged as efficient carriers,offering great potential for the cytoplasmic delivery of fluorescent probes in live cells.This review provides a comprehensive overview of CPPs as vehicles for probe delivery,outlining advances in their development,conjugation chemistries,and intracellular delivery mechanisms.Recent applications in live-cell imaging are highlighted and organized according to major CPP modification strategies,including sequence engineering,cyclization,hybrid design and enhancement by chemical reagents.Finally,the challenges that remain and the future outlook of this rapidly evolvingfield are discussed.展开更多
The outstanding performance of O3-type NaNi_(1/3)Fe_(1/3)Mn_(1/3)O_(2)(NFM111)at both high and low temperatures coupled with its impressive specific capacity makes it an excellent cathode material for sodium-ion batte...The outstanding performance of O3-type NaNi_(1/3)Fe_(1/3)Mn_(1/3)O_(2)(NFM111)at both high and low temperatures coupled with its impressive specific capacity makes it an excellent cathode material for sodium-ion batteries.However,its poor cycling,owing to highpressure phase transitions,is one of its disadvantages.In this study,Cu/Ti was introduced into NFM111 cathode material using a solidphase method.Through both theoretically and experimentally,this study found that Cu doping provides a higher redox potential in NFM111,improving its reversible capacity and charge compensation process.The introduction of Ti would enhance the cycling stability of the material,smooth its charge and discharge curves,and suppress its high-voltage phase transitions.Accordingly,the NaNi_(0.27)Fe_(0.28)Mn_(0.33)Cu_(0.05)Ti_(0.06)O_(2)sample used in the study exhibited a remarkable rate performance of 142.97 mAh·g^(-1)at 0.1 C(2.0-4.2 V)and an excellent capacity retention of 72.81%after 300 cycles at 1C(1C=150 mA·g^(-1)).展开更多
文摘Bicyclic peptides,a class of polypeptides with two loops within their structure,have emerged as powerful tools in the development of new peptide drugs.They have the potential to bind to challenged drug targets,with antibody-like affinity and selectivity.Meanwhile,bicyclic peptides possess small molecule-like access to chemical synthesis,which is conducive to large-scale synthesis and screening.In the last five years,bicyclic peptide technology has been increasingly developed,and researchers have carried out a variety of studies to elucidate the potential functions of bicyclic peptides.With the continuous development of synthetic methods and the advances of new technology to build bicyclic peptide libraries,bicyclic peptides are now becoming widely used in the development of new drugs for various diseases.This perspective provides an overview of the structure types,synthesis and applications of bicyclic peptides in current drug development,and our own views on future challenges of bicyclic peptides.
文摘From the ethanol extract of the roots of Brachystemma calycinum D. Don, a Chinese folk herb, four new minor cyclic peptides namely brachystemin A, B, C and D (1 - 4) have been isolated. Their structures were established as cyclo (Pro(1)-Phe-Leu-Ala(1)-Thr-Pro(2)-Ala(2)-Gly) (1), cyclo (Pro(1)-Ala-Phe-Trp-Asp-Pro(2)-Leu-Gly) (2), cyclo (Pro(1)-Ile-Gly-Pro(2)-Val-Ala(1)-Ala(2)-Tyr) (3) and cyclo ( Pro-OMet-Trp-Ile-Gly-Ala-Leu-Asp) (4) respectively by means of extensive spectral methods.
基金This work was supported by the National Natural Science Foundation of China(0072058)863 Foundation of China(2003AA624010)+2 种基金the National Natural Science Foundation of Guangdong Province,China(021732,2003A 3050401)a strategic grant at City University of Hong Kong(7000650)E.B.G.J.acknowledges the Royal Society,U.K.and City University of Hong Kong for the award of the Kan Tong Po Visiting Professorship.
文摘New cyclic peptides 1 and 2 were isolated from the endophytic fungus #2221 fromCastaniopsis fissa on the south China sea coast. By 2D NMR methods and chiral HPLC technique,their structures were elucidated as cyclo (L-Val-L-Leu-L-Val-L-Leu) and cyclo(L-Leu-L-Ala-L-Leu-L-Ala), respectively.
基金Grants from COMRA(Grant No.DY125-15-T-01 and SOA(Grant No.2010319123366025-4)National High Technology Development Project(863 Project,Grant No.2011AA10A202-2)National Key Technologies R&D Program(Grant No.2011BAE06B04)
文摘Chromatographic separation of the marine-derived bacterium Bacillus licheniformis resulted in the isolation of two new cyclic lipopeptides named ai-Cl6 surfactin （1） and ai-Cl4 surfactin （2）, together with iso-Cm5 surfactin and iso-Cl6 surfactin. The structures of the new cyclic lipopeptides were determined through extensive spectroscopic analysis. The sequences of the amino acids in cyclic nucleus were established by the ESI-MS/MS fragmentation, which provided an efficient method to detect lipopeptides from bacterium extracts without senaration
基金the National Key R&D Program of China(No.2022YFA1302900 to H.Liu)National Natural Science Foundation of China(Nos.82130105,22337003,82121005 to H.Liu+2 种基金and Nos.22177124,82322063 to J.Wang)Program of Shang-hai Academic Research Leader(No.23XD1460300 to J.Wang)the Lingang Laboratory(No.LG-GG-202204-02 to J.Wang)for supporting this work.We would like to acknowledge Shanghai Highline Therapeutics.
文摘Heterocycle-braced cyclic peptides have demonstrated enhanced metabolic stability,increased potency and selectivity.Here,we present a rapid synthesis method for constructing Trp(C7)-alkene(E)-crosslinked cyclic peptides with potent anti-proliferative activities against cancer cells,through C-H alkenylation and macrolactamization.This report addresses critical challenges associated with the installation and removal of the directing group N-Piv,configuration selectivity of the olefin,and intramolecular cyclization.No-tably,this method exhibits mild reaction conditions,traceless removal of the directing group,and high configuration selectivity.
基金This work was supported by State Key Laboratory of Bio-organic and Natural products Chemistry.
文摘We report here the synthesis of cyclic peptides using benzotriazolyloxy-bis(pyrrolidino)-carbonium hexafluoro- phosphate(BBC)as a coupling reagent with high yield and speed even in low concentration compared with the other usual coupling reagents.
文摘This paper reports the determination of stability constants for complexes of Cd(Ⅱ)with Gly, Ala,Val,Asp,Gly—Asp,Asp Gly,Gly—Gly and Gly—Gly—Gly using both micro—pH—metric titra- tions and the application of convolution—deconvolution cyclic voltammetry at 25℃ and I=0.10 mol· dm^(-3)(KNO_3).Stability constants were calculated from pH—metric data using the SUPERQUAD com- puter program and cyclic voltammograms were collected,stored and manipulated using the EG and G CONDECON 300 software.A considerably larger ligand:metal ratio(e,g.50:1)was possible using voltammetry.Evaluation of results from the two techniques suggests that stability constants for the species[CdL_2]and[CdL_3]are reliable when calculated fromvoltammetry while those for[CdL]are more reliable when determined by pH-metric titration.
文摘From Psammosilene tunicoides W. C. Wu et C. Y Wu, two cyclic octapeptides (namedpsammosilenins A and B) were isolated. Their structures were determined as cyclo(-Pro1-phe1-Pro2-Phe2-Phe3-Ala-Pro3-Leu-) and cyclo(-Pro1-Gly-Phe1-Val-Pro2-Phe2-Thr-Ile) by spectroscopicmethods.
基金Project supported by the Research Fund for the Doctoral Program of Higher Education.
文摘The interaction between HIV-1 DNA and five cyclic peptides （CP1-CP5） was investigated using electrospray ionization mass spectrometry （ESI-MS）. It revealed that CP1 [c（Ala-Tyr-Leu-Ala-Gly）] and CP4 [c（Pro-D-Tyr-Leu-D-Ala-Gly）] have the higher binding affinity with the duplex DNA among the five cyclic peptides.
基金supported by Principle Training Program of Education Department of Sichuan Province (No. 18CZ0042)Fundamental Research Fund of Chengdu University (No. 2081916027)Undergraduate Innovation Programm of Chengdu University (Nos. CDU_CX_2018250, CDU_CX_2018251)
文摘Protein-protein interactions(PPIs) are recognized as attractive therapeutic targets. However targeting PPIs especially intracellular ones has been proven extremely difficult for conventional drug-like small molecules, and biological drugs such as monoclonal antibodies have difficulty in reaching intracellular targets. Macrocyclic peptides are promising candidates of PPI regulators for their potential in combining high potency and biological stability together. Cell permeability of macrocyclic peptides may also be achieved by structural modifications or conjugation to a cell-penetrating sequence. Significant progress has been made in this research area in recent years. Important technology progress and recent examples of macrocyclic peptide PPI modulators are reviewed.
文摘Objective:To find potential peptide inhibitors against the NS2B/NS3 protease of DENV which in turn,can inhibit the viral replication inside host cell.Methods:Cyclic peptides were designed having combination of positively charged amino acids using ChemSketch software and were converted to 3D structures.DENV NS3 protein structure was retrieved from Protein Data Bank(PDB)using PDB Id:2FOM.DENV NS3 and cylic peptides were docked using MOE software after structural optimization.Results:Through molecular docking it was revealed that most of the peptides bound deeply in the binding pocket of DENV NS2B/NS3 protease an had interactions with catalytic triad.Peptide 2 successfully blocked the catalytic triad of NS2B/NS3 protease.Peptide 1,,4 and 6 also had potential interactions with active residues of the NS2B/NS3 protease while all other peptides were in close contact with the active sites of NS2B/NS3 protease thus,these peptides can serve as a potential drug candidate to stop viral replication.Conclusions:Thus.it can be concluded from the study that these peptides could serve as important inhibitors to inhibit the viral replication and need further in-vitro investigations to confirm their efficacy.
基金Universidad de Buenos Aires[UBACYT 2018-100246,PDE-48-2020],CONICET[PIP 11220200101898]and ANPCyT[PICT 2018-0930,PICT E 2018-0031]for partial financial support.
文摘The Antarctic fungus Cadophora malorum produces previously undescribed cyclic heptapeptides(cadophorin A and B)containing an anthranilic acid residue.The planar structure of these peptides was determined by high-resolution mass spectrometry combined with extensive 1D and 2D NMR spectroscopy.The absolute configuration of the amino acids was determined by Marfey’s method,with HPLC analysis of FDVA(Nα-(2,4-dinitro-5-fluorphenyl)-l-valinamide)derivatives making use of a PFP column.Remarkably,cadophorin 2 possesses both the uncommon d-Ile and d-allo-Ile in its structure.The peptides have metal binding properties as shown by LCMS with post column addition of metal salt solutions.These results were supported by DFT calculations.
文摘In biological controls using <em>Bacillus</em> spp., cyclic lipopeptides play a role as elicitors to induce disease resistance on various host plants. However, it is still unclear the specificity between cyclic lipopeptides and host plants to induce disease resistance. In this study, we aimed to clarify the specificity to induce disease resistance among cyclic lipopeptides on various host plants. Our data clearly showed both cyclic lipopeptides conferred disease suppression on most of host plants, but at different range of cyclic lipopeptide concentration. Our findings contribute to understanding the complex on the specificity of cyclic lipopeptide derived induced disease resistance.
基金supported by the National Natural Science Foundation of China(No.21472070)the Project for Jiangsu Scientific and Technological Innovation Team+2 种基金Fund for Jiangsu Distinguished Professorship ProgramProject Funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions,the 111 Project(No.111-2-06)the Jiangsu province“Collaborative Innovation Center for Advanced Industrial Fermentation”industry development program
文摘P-113 is a fragment of natural occurring peptide Histatin 5 found in human saliva. This peptide exhibited broad spectrum of antibacterial and antifungal biological activities. In this study, bifunctional P-113 peptides 2–5 were designed as Sortase A substrates and synthesized by solid support peptide synthesis,where the N-terminus were equipped with glycine and its analogues, and C-terminus were extended with LPETGGS, respectively. Under Sortase A catalyzed condition, head to tail cyclization products 7–10were afforded in yields from 76% to 93%. The conformation insights of linear peptides 2–5 and cyclic analogues 7–10 in aqueous buffers and in trifluroethanol（TFE） analyzed by circular dichroism（CD）suggested that a-helix structures were produced progressively in hydrophobic environment independent of the cyclization, which displayed the similar behavior as parent peptide P-113.
基金supported by National Natural Science Foundation of China(32370850,32460081)Leading Talent of Technological Innovation of Shaanxi Special Support Program(20249)+3 种基金the Natural Science Foundation of Shaanxi(2020JC-29,2023-JCZD-09)Central Universities Funds(GK202402003)the Jiangxi Agricultural University(9232308314)the Science and Technology Department of Jiangxi Province(20223BCJ25037)。
文摘Signaling peptides are known for their prominent roles in plant growth, development, and environmental adaptation(Zhang et al., 2025). However, their extremely low natural abundance and highly dynamic expression patterns pose significant technical challenges to extract sufficient amounts with good purity for biological studies and practical applications.Consequently, chemical synthesis and microbial systems offer attractive alternatives to obtain potent peptides at higher quantities and purity. Incorporating modifications or substitutions, chemically synthetic approaches enable the creation of more effective engineered peptides such as agonists,antagonists, chemically modified peptides, or peptide-like molecules with novel functions compared to native peptides.
基金Supported by the National Natural Science Foundation of China(Nos.52293472,22473096 and 22471164)。
文摘Among various architectures of polymers,end-group-free rings have attracted growing interests due to their distinct physicochemical performances over the linear counterparts which are exemplified by reduced hydrodynamic size and slower degradation.It is key to develop facile methods to large-scale synthesis of polymer rings with tunable compositions and microstructures.Recent progresses in large-scale synthesis of polymer rings against single-chain dynamic nanoparticles,and the example applications in synchronous enhancing toughness and strength of polymer nanocomposites are summarized.Once there is the breakthrough in rational design and effective large-scale synthesis of polymer rings and their functional derivatives,a family of cyclic functional hybrids would be available,thus providing a new paradigm in developing polymer science and engineering.
基金financially supported by the National Natural Science Foundation of China(No.22273026)Scientific Research Innovation Capability Support Project for Young Faculty(No.ZYGXQNJSKYCXNLZCXM-I15)+3 种基金Basic and Applied Basic Research Foundation of Guangdong Province(2024A1515012401)GJYC program of Guangzhou(No.2024D03J0002)the China Postdoctoral Science Foundation(No.2024M750938)Postdoctoral Fellowship Program of CPSF(No.GZC20240492)for their financial support。
文摘In contrast to cyclic polymers with ring-like backbones,side-chain cyclization is another intriguing structural feature that has not been extensively studied.In this study,a library of orthogonally protected monomers featuring monocyclic,dicyclic,or tricyclic pendant motifs was designed and prepared based on malic acid derivatives.Polyesters with precise chemical structures and uniform chain lengths were prepared modularly through iterative growth.Meticulous control over the chemical details allows for a close investigation of the topological effects on the polymer properties.Compared to their linear side chain counterparts,the presence of cyclic pendant groups has a significant impact on chain conformation,leading to a reduction in hydrodynamic volume and an enhancement in the glass transition temperature.These results underscore the potential of tailoring polymer properties through rational engineering of side chain topology.
基金support from the Joint Funds of the National Natural Science Foundation of China(Grant No.U23A2060)the National Natural Science Foundation of China(Grant Nos.42177143 and 52474150).
文摘Drilling and blasting tunneling is a cyclic process in which tunnel rock undergoes repeated blast loading,affecting its dynamic characteristics,energy evolution,and damage progression.To explore the dynamic mechanical properties and damage mechanisms of carbonaceous slate under cyclic impact loads of varying intensities,cyclic dynamic tests are conducted using a triaxial split Hopkinson pressure bar.This study analyzes the stress-strain relationship,energy damage evolution,and macro-to-micro failure characteristics.The results show that peak stress and strain are significantly influenced by impact intensity and the number of impacts.The initial dynamic stress is positively correlated with the impact intensity,but with more impact,the dynamic stress decreases while the peak strain increases.Energy evolution follows a pattern of"slow growthfluctuating growthrapid growth,"with the crack initiation stress and its proportion decreasing.CT and SEM analyses reveal that as the impact intensity increases,failure becomes more chaotic,the fracture volume increases,and the fracture mode shifts from interlayer and intergranular to through-layer and trans-granular fractures.These findings provide an experimental basis for soft rock tunnel stability analysis.
基金supported by the following grants:National Natural Science Foundation of China(Grant Nos.92354305 and 32271428),National Key R&D Program of China(Grant No.2022YFC3401100)Young Talent Program of Hubei Provincial Health Commission(WJ2025Q037)+1 种基金Interdisciplinary Research Program of HUST(Grant No.2023JCY5045)Director Fund of WNLO.
文摘Fluorescent probes,with their superior optical properties and labeling versatility,have greatly advanced the visualization of intracellular molecules and subcellular structures.However,poor cytoplasmic delivery,caused by charge,size,or targeting groups,limits the effective use of many fluorescent probes in live cells.Recently,cell-penetrating peptides(CPPs)have emerged as efficient carriers,offering great potential for the cytoplasmic delivery of fluorescent probes in live cells.This review provides a comprehensive overview of CPPs as vehicles for probe delivery,outlining advances in their development,conjugation chemistries,and intracellular delivery mechanisms.Recent applications in live-cell imaging are highlighted and organized according to major CPP modification strategies,including sequence engineering,cyclization,hybrid design and enhancement by chemical reagents.Finally,the challenges that remain and the future outlook of this rapidly evolvingfield are discussed.
基金supported by the Low-Cost Long-Life Batteries program,China(No.WL-24-08-01)the National Natural Science Foundation of China(No.22279007)。
文摘The outstanding performance of O3-type NaNi_(1/3)Fe_(1/3)Mn_(1/3)O_(2)(NFM111)at both high and low temperatures coupled with its impressive specific capacity makes it an excellent cathode material for sodium-ion batteries.However,its poor cycling,owing to highpressure phase transitions,is one of its disadvantages.In this study,Cu/Ti was introduced into NFM111 cathode material using a solidphase method.Through both theoretically and experimentally,this study found that Cu doping provides a higher redox potential in NFM111,improving its reversible capacity and charge compensation process.The introduction of Ti would enhance the cycling stability of the material,smooth its charge and discharge curves,and suppress its high-voltage phase transitions.Accordingly,the NaNi_(0.27)Fe_(0.28)Mn_(0.33)Cu_(0.05)Ti_(0.06)O_(2)sample used in the study exhibited a remarkable rate performance of 142.97 mAh·g^(-1)at 0.1 C(2.0-4.2 V)and an excellent capacity retention of 72.81%after 300 cycles at 1C(1C=150 mA·g^(-1)).
