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1.
J Am Chem Soc ; 146(1): 330-341, 2024 01 10.
Artículo en Inglés | MEDLINE | ID: mdl-38113388

RESUMEN

Implementing dissipative assembly in living systems is meaningful for creation of living materials or even artificial life. However, intracellular dissipative assembly remains scarce and is significantly impeded by the challenges lying in precisely operating chemical reaction cycles under complex physiological conditions. Here, we develop organelle-mediated dissipative self-assembly of peptides in living cells fueled by GSH, via the design of a mitochondrion-targeting and redox-responsive hexapeptide. While the hexapeptide undergoes efficient redox-responsive self-assembly, the addition of GSH into the peptide solution in the presence of mitochondrion-biomimetic liposomes containing hydrogen peroxide allows for transient assembly of peptides. Internalization of the peptide by LPS-stimulated macrophages leads to the self-assembly of the peptide driven by GSH reduction and the association of the peptide assemblies with mitochondria. The association facilitates reversible oxidation of the reduced peptide by mitochondrion-residing ROS and thereby dissociates the peptide from mitochondria to re-enter the cytoplasm for GSH reduction. The metastable peptide-mitochondrion complexes prevent the thermodynamically equilibrated self-assembly, thus establishing dissipative assembly of peptides in stimulated macrophages. The entire dissipative self-assembling process allows for elimination of elevated ROS and decrease of pro-inflammatory cytokine expression. Creating dissipative self-assembling systems assisted by internal structures provides new avenues for the development of living materials or medical agents in the future.


Asunto(s)
Mitocondrias , Péptidos , Especies Reactivas de Oxígeno , Péptidos/química
2.
J Am Chem Soc ; 146(15): 10753-10766, 2024 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-38578841

RESUMEN

Proteolysis targeting chimera (PROTAC) technology is an innovative strategy for cancer therapy, which, however, suffers from poor targeting delivery and limited capability for protein of interest (POI) degradation. Here, we report a strategy for the in situ formulation of antineoplastic Supra-PROTACs via intracellular sulfatase-responsive assembly of peptides. Coassembling a sulfated peptide with two ligands binding to ubiquitin VHL and Bcl-xL leads to the formation of a pro-Supra-PROTAC, in which the ratio of the two ligands is rationally optimized based on their protein binding affinity. The resulting pro-Supra-PROTAC precisely undergoes enzyme-responsive assembly into nanofibrous Supra-PROTACs in cancer cells overexpressing sulfatase. Mechanistic studies reveal that the pro-Supra-PROTACs selectively cause apparent cytotoxicity to cancer cells through the degradation of Bcl-xL and the activation of caspase-dependent apoptosis, during which the rationally optimized ligand ratio improves the bioactivity for POI degradation and cell death. In vivo studies show that in situ formulation enhanced the tumor accumulation and retention of the pro-Supra-PROTACs, as well as the capability for inhibiting tumor growth with excellent biosafety when coadministrating with chemodrugs. Our findings provide a new approach for enzyme-regulated assembly of peptides in living cells and the development of PROTACs with high targeting delivering and POI degradation efficiency.


Asunto(s)
Antineoplásicos , Neoplasias , Humanos , Quimera Dirigida a la Proteólisis , Antineoplásicos/farmacología , Sulfatasas , Proteolisis , Péptidos , Ubiquitina-Proteína Ligasas
3.
Biomacromolecules ; 25(4): 2497-2508, 2024 Apr 08.
Artículo en Inglés | MEDLINE | ID: mdl-38478850

RESUMEN

Morphology-transformational self-assembly of peptides allows for manipulation of the performance of nanostructures and thereby advancing the development of biomaterials. Acceleration of the morphological transformation process under a biological microenvironment is important to efficiently implement the tailored functions in living systems. Herein, we report redox-regulated in situ seed-induced assembly of peptides via design of two co-assembled bola-amphiphiles serving as a redox-resistant seed and a redox-responsive assembly monomer, respectively. Both of the peptides are able to independently assemble into nanoribbons, while the seed monomer exhibits stronger assembling propensity. The redox-responsive monomer undergoes morphological transformation from well-defined nanoribbons to nanoparticles. Kinetics studies validate the role of the assembled inert monomer as the seeds in accelerating the assembly of the redox-responsive monomer. Alternative addition of oxidants and reductants into the co-assembled monomers promotes the redox-regulated assembly of the peptides facilitated by the in situ-formed seeds. The reduction-induced assembly of the peptide could also be accelerated by in situ-formed seeds in cancer cells with a high level of reductants. Our findings demonstrate that through precisely manipulating the assembling propensity of co-assembled monomers, the in situ seed-induced assembly of peptides could be achieved. Combining the rapid assembly kinetics of the seed-induced assembly with the common presence of redox agents in a biological microenvironment, this strategy potentially offers a new method for developing biomedical materials in living systems.


Asunto(s)
Nanoestructuras , Nanotubos de Carbono , Sustancias Reductoras , Péptidos/química , Nanoestructuras/química , Materiales Biocompatibles , Oxidación-Reducción
4.
Angew Chem Int Ed Engl ; 63(28): e202404703, 2024 07 08.
Artículo en Inglés | MEDLINE | ID: mdl-38655625

RESUMEN

Self-assembly in living cells represents one versatile strategy for drug delivery; however, it suffers from the limited precision and efficiency. Inspired by viral traits, we here report a cascade targeting-hydrolysis-transformation (THT) assembly of glycosylated peptides in living cells holistically resembling viral infection for efficient cargo delivery and combined tumor therapy. We design a glycosylated peptide via incorporating a ß-galactose-serine residue into bola-amphiphilic sequences. Co-assembling of the glycosylated peptide with two counterparts containing irinotecan (IRI) or ligand TSFAEYWNLLSP (PMI) results in formation of the glycosylated co-assemblies SgVEIP, which target cancer cells via ß-galactose-galectin-1 association and undergo galactosidase-induced morphological transformation. While GSH-reduction causes release of IRI from the co-assemblies, the PMI moieties release p53 and facilitate cell death via binding with protein MDM2. Cellular experiments show membrane targeting, endo-/lysosome-mediated internalization and in situ formation of nanofibers in cytoplasm by SgVEIP. This cascade THT process enables efficient delivery of IRI and PMI into cancer cells secreting Gal-1 and overexpressing ß-galactosidase. In vivo studies illustrate enhanced tumor accumulation and retention of the glycosylated co-assemblies, thereby suppressing tumor growth. Our findings demonstrate an in situ assembly strategy mimicking viral infection, thus providing a new route for drug delivery and cancer therapy in the future.


Asunto(s)
Sistemas de Liberación de Medicamentos , Glicopéptidos , Humanos , Glicopéptidos/química , Glicopéptidos/metabolismo , Animales , Virosis/tratamiento farmacológico , Virosis/metabolismo , Irinotecán/química , Irinotecán/farmacología , Ratones , Línea Celular Tumoral
5.
Chembiochem ; 24(3): e202200497, 2023 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-36278304

RESUMEN

In situ self-assembly of peptides into well-defined nanostructures represents one of versatile strategies for creation of bioactive materials within living cells with great potential in disease diagnosis and treatment. The intimate relationship between amino acid sequences and the assembling propensity of peptides has been thoroughly elucidated over the past few decades. This has inspired development of various controllable self-assembling peptide systems based on stimuli-responsive naturally occurring or non-canonical amino acids, including redox-, pH-, photo-, enzyme-responsive amino acids. This review attempts to summarize the recent progress achieved in manipulating in situ self-assembly of peptides by controllable reactions occurring to amino acids. We will highlight the systems containing non-canonical amino acids developed in our laboratory during the past few years, primarily including acid/enzyme-responsive 4-aminoproline, redox-responsive (seleno)methionine, and enzyme-responsive 2-nitroimidazolyl alanine. Utilization of the stimuli-responsive assembling systems in creation of bioactive materials will be specifically introduced to emphasize their advantages for addressing the concerns lying in disease theranostics. Eventually, we will provide the perspectives for the further development of stimulus-responsive amino acids and thereby demonstrating their great potential in development of next-generation biomaterials.


Asunto(s)
Aminoácidos , Nanoestructuras , Aminoácidos/química , Péptidos/química , Secuencia de Aminoácidos , Nanoestructuras/química , Materiales Biocompatibles/química
6.
Macromol Rapid Commun ; 44(23): e2300308, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37462116

RESUMEN

Bio-inspired design of peptides represents one facile strategy for development of supramolecular monomers for self-assembly into well-defined nanostructures. Inspired by methylation of arginine during post-translational modification for manipulating protein functions, herein, the controllable self-assembly of peptides via rational incorporation of methylated arginine residues into bola-amphiphilic peptides is reported. A series of bola-amphiphilic peptides are designed and synthesized either containing natural arginine or methylated arginine and investigate the influence of arginine methylation on peptide assembly. This study finds that incorporation of symmetrically di-methylated arginine into oppositely charged hexapeptide hex-SDMAE leads to distinct assembling performance compare to natural peptide hex-RE. The findings demonstrate that the methylation of rationally designed peptide sequences allows for regulation of self-assembly of peptides, thus implying the great potential of arginine methylation in establishing controllable peptide assembling systems and creating in situ formulation of biomedical materials in the future.


Asunto(s)
Arginina , Péptidos , Arginina/química , Péptidos/química , Proteínas , Procesamiento Proteico-Postraduccional , Metilación
7.
Angew Chem Int Ed Engl ; 62(49): e202314578, 2023 12 04.
Artículo en Inglés | MEDLINE | ID: mdl-37870078

RESUMEN

The presence of disordered region or large interacting surface within proteins significantly challenges the development of targeted drugs, commonly known as the "undruggable" issue. Here, we report a heterogeneous peptide-protein assembling strategy to selectively phosphorylate proteins, thereby activating the necroptotic signaling pathway and promoting cell necroptosis. Inspired by the structures of natural necrosomes formed by receptor interacting protein kinases (RIPK) 1 and 3, the kinase-biomimetic peptides are rationally designed by incorporating natural or D -amino acids, or connecting D -amino acids in a retro-inverso (DRI) manner, leading to one RIPK3-biomimetic peptide PR3 and three RIPK1-biomimetic peptides. Individual peptides undergo self-assembly into nanofibrils, whereas mixing RIPK1-biomimetic peptides with PR3 accelerates and enhances assembly of PR3. In particular, RIPK1-biomimetic peptide DRI-PR1 exhibits reliable binding affinity with protein RIPK3, resulting in specific cytotoxicity to colon cancer cells that overexpress RIPK3. Mechanistic studies reveal the increased phosphorylation of RIPK3 induced by RIPK1-biomimetic peptides, elucidating the activation of the necroptotic signaling pathway responsible for cell death without an obvious increase in secretion of inflammatory cytokines. Our findings highlight the potential of peptide-protein hybrid aggregation as a promising approach to address the "undruggable" issue and provide alternative strategies for overcoming cancer resistance in the future.


Asunto(s)
Apoptosis , Péptidos , Apoptosis/fisiología , Muerte Celular , Fosforilación , Péptidos/farmacología , Aminoácidos
8.
Plant J ; 108(5): 1346-1364, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34582078

RESUMEN

Tiller angle is an important determinant of plant architecture in rice (Oryza sativa L.). Auxins play a critical role in determining plant architecture; however, the underlying metabolic and signaling mechanisms are still largely unknown. In this study, we have identified a member of the bZIP family of TGA class transcription factors, OsbZIP49, that participates in the regulation of plant architecture and is specifically expressed in gravity-sensing tissues, including the shoot base, nodes and lamina joints. Transgenic rice plants overexpressing OsbZIP49 displayed a tiller-spreading phenotype with reduced plant height and internode lengths. In contrast, CRISPR/Cas9-mediated knockout of OsbZIP49 resulted in a compact architecture. Follow-up studies indicated that the effects of OsbZIP49 on tiller angles are mediated through changes in shoot gravitropic responses. Additionally, we provide evidence that OsbZIP49 activates the expression of indole-3-acetic acid-amido synthetases OsGH3-2 and OsGH3-13 by directly binding to TGACG motifs located within the promoters of both genes. Increased GH3-catalyzed conjugation of indole-3-acetic acid (IAA) in rice transformants overexpressing OsbZIP49 resulted in the increased accumulation of IAA-Asp and IAA-Glu, and a reduction in local free auxin, tryptamine and IAA-Glc levels. Exogenous IAA or naphthylacetic acid (NAA) partially restored shoot gravitropic responses in OsbZIP49-overexpressing plants. Knockout of OsbZIP49 led to reduced expression of both OsGH3-2 and OsGH3-13 within the shoot base, and increased accumulation of IAA and increased OsIAA20 expression levels were observed in transformants following gravistimulation. Taken together, the present results reveal the role transcription factor OsbZIP49 plays in determining plant architecture, primarily due to its influence on local auxin homeostasis.


Asunto(s)
Ácidos Indolacéticos/metabolismo , Oryza/genética , Reguladores del Crecimiento de las Plantas/metabolismo , Proteínas de Plantas/metabolismo , Expresión Génica , Técnicas de Inactivación de Genes , Gravitropismo , Homeostasis , Complejos Multienzimáticos/genética , Complejos Multienzimáticos/metabolismo , Oryza/crecimiento & desarrollo , Fenotipo , Proteínas de Plantas/genética , Plantas Modificadas Genéticamente , Regiones Promotoras Genéticas/genética , Factores de Transcripción/genética , Factores de Transcripción/metabolismo
9.
J Am Chem Soc ; 144(21): 9312-9323, 2022 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-35587998

RESUMEN

Self-sorting is a common phenomenon in eukaryotic cells and represents one of the versatile strategies for the formation of advanced functional materials; however, developing artificial self-sorting assemblies within living cells remains challenging. Here, we report on the GSH-responsive in situ self-sorting peptide assemblies within cancer cells for simultaneous organelle targeting to promote combinatorial organelle dysfunction and thereby cell death. The self-sorting system was created via the design of two peptides E3C16E6 and EVMSeO derived from lipid-inspired peptide interdigitating amphiphiles and peptide bola-amphiphiles, respectively. The distinct organization patterns of the two peptides facilitate their GSH-induced self-sorting into isolated nanofibrils as a result of cleavage of disulfide-connected hydrophilic domains or reduction of selenoxide groups. The GSH-responsive in situ self-sorting in the peptide assemblies within HeLa cells was directly characterized by super-resolution structured illumination microscopy. Incorporation of the thiol and ER-targeting groups into the self-sorted assemblies endows their simultaneous targeting of endoplasmic reticulum and Golgi apparatus, thus leading to combinatorial organelle dysfunction and cell death. Our results demonstrate the establishment of the in situ self-sorting peptide assemblies within living cells, thus providing a unique platform for drug targeting delivery and an alternative strategy for modulating biological processes in the future.


Asunto(s)
Aparato de Golgi , Péptidos , Retículo Endoplásmico/metabolismo , Aparato de Golgi/metabolismo , Células HeLa , Humanos , Péptidos/química , Transporte de Proteínas
10.
J Am Chem Soc ; 144(15): 6907-6917, 2022 04 20.
Artículo en Inglés | MEDLINE | ID: mdl-35388694

RESUMEN

Enzyme-regulated in situ self-assembly of peptides represents one versatile strategy in the creation of theranostic agents, which, however, is limited by the strong dependence on enzyme overexpression. Herein, we reported the self-amplifying assembly of peptides precisely in macrophages associated with enzyme expression for improving the anti-inflammatory efficacy of conventional drugs. The self-amplifying assembling system was created via coassembling an enzyme-responsive peptide with its derivative functionalized with a protein ligand. Reduction of the peptides by the enzyme NAD(P)H quinone dehydrogenase 1 (NQO1) led to the formation of nanofibers with high affinity to the protein, thereby facilitating NQO1 expression. The improved NQO1 level conversely promoted the assembly of the peptides into nanofibers, thus establishing an amplifying relationship between the peptide assembly and the NQO1 expression in macrophages. Utilization of the amplifying assembling system as vehicles for drug dexamethasone allowed for its passive targeting delivery to acute injured lungs. Both in vitro and in vivo studies confirmed the capability of the self-amplifying assembling system to enhance the anti-inflammatory efficacy of dexamethasone via simultaneous alleviation of the reactive oxygen species side effect and downregulation of proinflammatory cytokines. Our findings demonstrate the manipulation of the assembly of peptides in living cells with a regular enzyme level via a self-amplification process, thus providing a unique strategy for the creation of supramolecular theranostic agents in living cells.


Asunto(s)
Nanofibras , Péptidos , Dexametasona , Ligandos , Macrófagos/metabolismo , Nanofibras/química , Péptidos/química
11.
J Nanobiotechnology ; 20(1): 340, 2022 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-35858873

RESUMEN

Practice of tumor-targeted suicide gene therapy is hampered by unsafe and low efficient delivery of plasmid DNA (pDNA). Using HIV-Tat-derived peptide (Tat) to non-covalently form Tat/pDNA complexes advances the delivery performance. However, this innovative approach is still limited by intracellular delivery efficiency and cell-cycle status. In this study, Tat/pDNA complexes were further condensed into smaller, nontoxic nanoparticles by Ca2+ addition. Formulated Tat/pDNA-Ca2+ nanoparticles mainly use macropinocytosis for intercellular delivery, and their macropinocytic uptake was persisted in mitosis (M-) phase and highly activated in DNA synthesis (S-) phase of cell-cycle. Over-expression or phosphorylation of a mitochondrial chaperone, 75-kDa glucose-regulated protein (GRP75), promoted monopolar spindle kinase 1 (MPS1)-controlled centrosome duplication and cell-cycle progress, but also driven cell-cycle-dependent macropinocytosis of Tat/pDNA-Ca2+ nanoparticles. Further in vivo molecular imaging based on DF (Fluc-eGFP)-TF (RFP-Rluc-HSV-ttk) system showed that Tat/pDNA-Ca2+ nanoparticles exhibited highly suicide gene therapy efficiency in mouse model xenografted with human ovarian cancer. Furthermore, arresting cell-cycle at S-phase markedly enhanced delivery performance of Tat/pDNA-Ca2+ nanoparticles, whereas targeting GRP75 reduced their macropinocytic delivery. More importantly, in vivo targeting GRP75 combined with cell-cycle or macropinocytosis inhibitors exhibited distinct suicide gene therapy efficiency. In summary, our data highlight that mitochondrial chaperone GRP75 moonlights as a biphasic driver underlying cell-cycle-dependent macropinocytosis of Tat/pDNA-Ca2+ nanoparticles in ovarian cancer.


Asunto(s)
Nanopartículas , Neoplasias Ováricas , Animales , Calcio , ADN/química , Femenino , Técnicas de Transferencia de Gen , Terapia Genética , Proteínas HSP70 de Choque Térmico , Humanos , Proteínas de la Membrana , Ratones , Nanopartículas/química , Neoplasias Ováricas/terapia , Plásmidos , Transfección
12.
Nano Lett ; 21(13): 5730-5737, 2021 07 14.
Artículo en Inglés | MEDLINE | ID: mdl-34142834

RESUMEN

Mitochondrion-targeting therapy exhibits great potential in cancer therapy but significantly suffers from limited therapeutic efficiency. Here we report on mitochondrion-targeting supramolecular antagonist-inducing tumor cell death via simultaneously promoting cellular apoptosis and preventing survival. The supramolecular antagonist was created via coassembly of a mitochondrion-targeting pentapeptide with its two derivatives functionalized with a BH3 domain or the drug camptothecin (CPT). While drug CPT released from the antagonist induced cellular apoptosis via decreasing the mitochondrial membrane potential, the BH3 domain prevented cellular survival through facilitating the association between the supramolecular antagonists and antiapoptotic proteins, thereby initiating mitochondrial permeabilization. Both in vitro and in vivo studies confirmed the combinatorial therapeutic effect arising from the BH3 domain and CPT drug within the supramolecular antagonist on cell death and thereby inhibiting tumor growth. Our findings demonstrate an efficient combinatorial mechanism for mitochondrial dysfunction, thus potentially serving as novel organelle-targeting medicines.


Asunto(s)
Apoptosis , Camptotecina , Camptotecina/farmacología , Mitocondrias
13.
J Am Chem Soc ; 143(34): 13854-13864, 2021 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-34410694

RESUMEN

Design of endogenous stimuli-responsive amino acids allows for precisely modulating proteins or peptides under a biological microenvironment and thereby regulating their performance. Herein we report a noncanonical amino acid 2-nitroimidazol-1-yl alanine and explore its functions in creation of the nitroreductase (NTR)-responsive peptide-based supramolecular probes for efficient hypoxia imaging. On the basis of the reduction potential of the nitroimidazole unit, the amino acid was synthesized via the Mitsunobu reaction between 2-nitroimidazole and a serine derivate. We elucidated the relationship between the NTR-responsiveness of the amino acid and the structural feature of peptides involving a series of peptides. This eventually facilitates development of aromatic peptides undergoing NTR-responsive self-assembly by rationally optimizing the sequences. Due to the intrinsic role of 2-nitroimidazole in the fluorescence quench, we created a morphology-transformable supramolecular probe for imaging hypoxic tumor cells based on NTR reduction. We found that the resulting supramolecular probes penetrated into solid tumors, thus allowing for efficient fluorescence imaging of tumor cells in hypoxic regions. Our findings demonstrate development of a readily synthesized and versatile amino acid with exemplified properties in creating fluorescent peptide nanostructures responsive to a biological microenvironment, thus providing a powerful toolkit for synthetic biology and development of novel biomaterials.


Asunto(s)
Aminoácidos/metabolismo , Péptidos/metabolismo , Alanina/química , Alanina/metabolismo , Aminoácidos/química , Animales , Neoplasias de la Mama/patología , Línea Celular Tumoral , Femenino , Colorantes Fluorescentes/química , Ratones , Microscopía Confocal , Nitroimidazoles/química , Nitrorreductasas/metabolismo , Imagen Óptica , Péptidos/química , Trasplante Homólogo
14.
Nano Lett ; 19(11): 7965-7976, 2019 11 13.
Artículo en Inglés | MEDLINE | ID: mdl-31596096

RESUMEN

Nanomedicines have been demonstrated as promising strategies for cancer therapy due to the advantages in pharmacokinetics and drug targeting delivery to tumor tissues. However, creation of delivery platforms able to intrinsically and spatially optimize drug cellular uptake during the entire delivering process remain challenging. To address this challenge, here we report on tumor microenvironment-adaptable self-assembly (TMAS) of pentapeptides regulated by the pH-sensitive cis/trans isomerization of 4-amino-proline (Amp) amide bonds for enhanced drug delivery and photodynamic therapeutic (PDT) efficacy. We found that decreasing solution pH led to the cis → trans isomerization of Amp amide bonds, thus promoting reversible self-assembly of pentapeptide FF-Amp-FF (AmpF) into superhelices and nanoparticles upon alternating exposure to neutral and mild acidic conditions. Co-assembly of peptide AmpF with its derivative containing a photosensitizer Chlorin e6 (AmpF-C) allows for creation of TMAS systems undergoing a morphological transition adaptable to the pH gradient present in cellular uptake pathway. Ex vivo studies revealed that TMAS nanomedicines prolonged circulation in the animal body and improved accumulation at tumor sites compared to morphology-persistent nanomedicines. In addition to the optimized cellular uptake, the morphological transition of TMAS into nanofibers in cytoplasm caused an enhanced intracellular ROS level compared to nanoparticle counterparts, thus leading to a lowered half lethal dose value for cancer cells. The combined advantages of TMAS eventually allowed in vivo PDT therapy for significant inhibition of tumor growth, thus demonstrating the improved drug delivery efficiency and therapeutic efficacy of TMAS systems toward new-generation nanomedicines.


Asunto(s)
Neoplasias de la Mama/tratamiento farmacológico , Preparaciones de Acción Retardada/química , Oligopéptidos/química , Fármacos Fotosensibilizantes/administración & dosificación , Porfirinas/administración & dosificación , Prolina/química , Animales , Neoplasias de la Mama/patología , Supervivencia Celular/efectos de los fármacos , Clorofilidas , Femenino , Isomerismo , Ratones , Nanoestructuras/química , Fotoquimioterapia , Fármacos Fotosensibilizantes/uso terapéutico , Porfirinas/uso terapéutico , Microambiente Tumoral/efectos de los fármacos
15.
Langmuir ; 35(13): 4710-4717, 2019 04 02.
Artículo en Inglés | MEDLINE | ID: mdl-30836752

RESUMEN

Precise incorporation of functional residues into sequences allows for tailoring the noncovalent interactions between peptides to guide their self-assembly into well-defined nanostructures, thus facilitating creation of artificial functional materials resembling natural systems. Here, we report on the self-assembly of dipeptides consisting of one fluorinated phenylalanine unit (Z residue) and one natural aromatic residue into laminated nanofibers predominately driven by polar-π interactions. On the basis of characterizations using transmission electron microscopy, scanning electron microscopy, atomic force microscopy, circular dichroism, Fourier transform infrared spectroscopy, and thioflavin T binding assay, we found that the face-centered stacking pattern of the dipeptides FZ, ZF, and ZY stabilized by the polar-π interactions and antiparallel ß-sheet H-bonding interactions led to lamination of nanofibers and formation of ribbonlike nanostructures. Our findings demonstrate that incorporation of fluorinated aromatic units into short peptides not only promotes of polar-π interactions as alternative self-assembling driving forces but also governs the organizing pattern of peptides, thus benefiting creation of well-defined peptide nanostructures.

16.
J Am Chem Soc ; 139(23): 7823-7830, 2017 06 14.
Artículo en Inglés | MEDLINE | ID: mdl-28571316

RESUMEN

Co-assembly of binary systems driven by specific non-covalent interactions can greatly expand the structural and functional space of supramolecular nanostructures. We report here on the self-assembly of peptide amphiphiles and fatty acids driven primarily by anion-π interactions. The peptide sequences investigated were functionalized with a perfluorinated phenylalanine residue to promote anion-π interactions with carboxylate headgroups in fatty acids. These interactions were verified here by NMR and circular dichroism experiments as well as investigated using atomistic simulations. Positioning the aromatic units close to the N-terminus of the peptide backbone near the hydrophobic core of cylindrical nanofibers leads to strong anion-π interactions between both components. With a low content of dodecanoic acid in this position, the cylindrical morphology is preserved. However, as the aromatic units are moved along the peptide backbone away from the hydrophobic core, the interactions with dodecanoic acid transform the cylindrical supramolecular morphology into ribbon-like structures. Increasing the ratio of dodecanoic acid to PA leads to either the formation of large vesicles in the binary systems where the anion-π interactions are strong, or a heterogeneous mixture of assemblies when the peptide amphiphiles associate weakly with dodecanoic acid. Our findings reveal how co-assembly involving designed specific interactions can drastically change supramolecular morphology and even cross from nano to micro scales.


Asunto(s)
Ácidos Láuricos/química , Lípidos/química , Nanoestructuras/química , Péptidos/química , Tensoactivos/química , Aniones/química , Interacciones Hidrofóbicas e Hidrofílicas , Sustancias Macromoleculares/química , Conformación Molecular , Simulación de Dinámica Molecular
17.
Nano Lett ; 16(11): 6967-6974, 2016 11 09.
Artículo en Inglés | MEDLINE | ID: mdl-27797531

RESUMEN

Asymmetry in chemical structure or shape at molecular, nanoscale, or microscopic levels is essential to a vast number of functionalities in both natural and artificial systems. Bottom-up approaches to create asymmetric supramolecular nanostructures are considered promising but this strategy suffers from the potentially dynamic nature of noncovalent interactions. We report here on supramolecular self-assembly of asymmetric peptide amphiphiles consisting of two different molecularly linked domains. We found that strong noncovalent interactions and a high degree of internal order among the asymmetric amphiphiles lead to nanoribbons with asymmetric faces due to the preferential self-association of the two domains. The capture of gold nanoparticles on only one face of the nanoribbons demonstrates symmetry breaking in these supramolecular structures.


Asunto(s)
Nanotubos de Carbono/química , Péptidos/química , Cloruro de Calcio/química , Electrones , Oro/química , Interacciones Hidrofóbicas e Hidrofílicas , Nanopartículas del Metal/química , Tamaño de la Partícula , Conformación Proteica , Multimerización de Proteína , Reología , Propiedades de Superficie , Termodinámica
18.
J Am Chem Soc ; 138(39): 12997-13005, 2016 10 05.
Artículo en Inglés | MEDLINE | ID: mdl-27598007

RESUMEN

Investigating and deciphering the dynamics of photoswitchable foldamers provides a detailed understanding of their photoinduced conformational transitions, resembling similar processes in photoresponsive biomacromolecules. We studied the ultrafast dynamics of the photoisomerization of azobenzene moieties embedded in a foldamer backbone and the resulting conformational helix-coil transition by time-resolved femtosecond/picosecond pump-probe spectroscopy in the visible and infrared region. During E → Z photoisomerization of the azobenzenes, the complexity of the photoinduced conformational transition of the pentameric foldamer 105 is reflected in distinct spectral characteristics and a 2-fold slower decay of the excited-state absorption bands compared to the monomer M (τ4,foldamer = 20 ps, τ4,monomer = 9 ps). Time-resolved IR experiments reveal the vibrational features of the monomer and the foldamer after photoexcitation, with an additional time constant for the foldamer (τ = 150 ps), indicating the initial steps of unfolding of the helical conformation, which are supported by density functional theory calculations. Our results record the overall sequence of photoinduced structural changes in the foldamer, starting from the initial ultrafast isomerization of the azobenzene unit(s) and ending with the complete unfolding on a later time scale. From our experiments, we could gain insight into the coupling of primary photoisomerization events ("cause") and secondary unfolding processes ("effect") in these oligoazobenzene foldamers.

19.
J Mater Chem B ; 12(18): 4289-4306, 2024 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-38595070

RESUMEN

The past few decades have witnessed substantial progress in biomedical materials for addressing health concerns and improving disease therapeutic and diagnostic efficacy. Conventional biomedical materials are typically created through an ex vivo approach and are usually utilized under physiological environments via transfer from preparative media. This transfer potentially gives rise to challenges for the efficient preservation of the bioactivity and implementation of theranostic goals on site. To overcome these issues, the in situ synthesis of biomedical materials on site has attracted great attention in the past few years. Peptides, which exhibit remarkable biocompability and reliable noncovalent interactions, can be tailored via tunable assembly to precisely create biomedical materials. In this review, we summarize the progress in the self-assembly of peptides in living cells for disease diagnosis and therapy. After a brief introduction to the basic design principles of peptide assembly systems in living cells, the applications of peptide assemblies for bioimaging and disease treatment are highlighted. The challenges in the field of peptide self-assembly in living cells and the prospects for novel peptide assembly systems towards next-generation biomaterials are also discussed, which will hopefully help elucidate the great potential of peptide assembly in living cells for future healthcare applications.


Asunto(s)
Materiales Biocompatibles , Péptidos , Nanomedicina Teranóstica , Humanos , Péptidos/química , Péptidos/síntesis química , Materiales Biocompatibles/química , Materiales Biocompatibles/síntesis química , Materiales Biocompatibles/farmacología , Animales
20.
J Imaging ; 10(7)2024 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-39057736

RESUMEN

In the sphere of urban renewal of historic districts, preserving and innovatively reinterpreting traditional architectural styles remains a primary research focus. However, the modernization and adaptive reuse of traditional buildings often necessitate changes in their functionality. To cater to the demands of tourism in historic districts, many traditional residential buildings require conversion to commercial use, resulting in a mismatch between their external form and their internal function. This study explored an automated approach to transform traditional residences into commercially viable designs, offering an efficient and scalable solution for the modernization of historic architecture. We developed a methodology based on diffusion models, focusing on a dataset of nighttime shopfront facades. By training a low-rank adaptation (LoRA) model and integrating the ControlNet model, we enhanced the accuracy and stability of the generated images. The methodology's performance was validated through qualitative and quantitative assessments, optimizing the batch size, repetition, and learning rate configurations. These evaluations confirmed the method's effectiveness. Our findings significantly advance the modern commercial style transformation of historical architectural facades, providing a novel solution that maintains the aesthetic and functional integrity, thereby fostering breakthroughs in traditional design thinking and exploring new possibilities for the preservation and commercial adaptation of historical buildings.

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