RESUMEN
As a development of our research on biocompatible glycoconjugate probes and specifically multi-chromophoric systems, herein, we report the synthesis and early bactericidal tests of two luminescent glycoconjugates whose basic structure is characterized by two boron dipyrromethene difluoride (BODIPY) moieties and three galactoside rings mounted on an oligophenylene ethynylene (OPE) skeleton. BODIPY fluorophores have found widespread application in many branches of biology in the last few decades. In particular, molecular platforms showing two different BODIPY groups have unique photophysical behavior useful in fluorescence imaging. Construction of the complex architecture of the new probes is accomplished through a convergent route that exploits a series of copper-free Heck-Cassar-Sonogashira cross-couplings. The great emergency due to the proliferation of bacterial infections, in conjunction with growing antibiotic resistance, requires the production of new multifunctional drugs and efficient methods for their targeted delivery to control bacteria-associated diseases. Preliminary studies of the glycoconjugate properties as antibacterial agents against representatives of Gram-negative (P. aeruginosa) and Gram-positive (S. aureus) pathogens, which are associated with chronic infections, indicated significant bactericidal activity ascribable to their structural features.
Asunto(s)
Antibacterianos , Compuestos de Boro , Pruebas de Sensibilidad Microbiana , Pseudomonas aeruginosa , Compuestos de Boro/química , Compuestos de Boro/farmacología , Compuestos de Boro/síntesis química , Antibacterianos/farmacología , Antibacterianos/química , Antibacterianos/síntesis química , Pseudomonas aeruginosa/efectos de los fármacos , Staphylococcus aureus/efectos de los fármacos , Glicoconjugados/química , Glicoconjugados/farmacología , Glicoconjugados/síntesis química , Estructura Molecular , Colorantes Fluorescentes/química , Colorantes Fluorescentes/síntesis químicaRESUMEN
Natural honey contains glycoconjugates as minor components. We characterized acacia honey glycoconjugates with molecular masses in the range of 2-5 kDa. The glycoconjugates were separated by RP-HPLC into three peaks (termed RP-2-5 k-I, RP-2-5 k-II, and RP-2-5 k-III) which demonstrated paralyzing effects on the model nematode C. elegans (ED50 of 50 ng glycoconjugates/µL). To examine molecular mechanisms underlying the nematicidal effects of honey glycoconjugates, expressional analyses of genes that are essential for the growth, development, reproduction, and movement of C. elegans were carried out. Quantitative PCR-based assays showed that these molecules moderately regulate the expression of genes involved in the citric acid cycle (mdh-1 and idhg-1) and cytoskeleton (act-1 and act-2). MALDI-ToF-MS/MS analysis of RP-HPLC peaks revealed the presence of paucimannose-like N-glycans which are known to play important roles in invertebrates e.g., worms and flies. These findings provided novel information regarding the structure and nematicidal function of honey glycoconjugates.
Asunto(s)
Acacia , Miel , Animales , Abejas , Miel/análisis , Caenorhabditis elegans , Espectrometría de Masas en Tándem , Antinematodos/farmacología , Glicoconjugados/farmacologíaRESUMEN
Galactose as a recognizing motif for asialoglycoprotein receptor (ASGPR) is a widely accepted vector to deliver cytotoxic agents in the therapy of hepatocellular carcinoma (HCC), however, the individual hydroxyl group of galactose (Gal) contributed to recognizing ASGPR is obscure and remains largely unanswered in the design of glycoconjugates. Herein, we designed and synthesized five positional isomers of Gal-anthocyanin Cy5.0 conjugates and three Gal-doxorubicin (Dox) isomers, respectively. The fluorescence intensity of Gal-Cy5.0 conjugates accumulated in cancer cells hinted the optimal modification sites of positions C2 and C6. Comparing to the cytotoxicity of other conjugates, C2-Gal-Dox (11) was the most potent. Moreover, Gal-Dox conjugates significantly the toxicity of Dox. A progressively lower internalization capacity and siRNA technology implied the cellular uptake and cytotoxicity directly related to the ASGPR expression level. Accordingly, position C2 of galactose may be the best substitution site via ASGPR mediation in the design of anti-HCC glycoconjugates.
Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/patología , Galactosa , Receptor de Asialoglicoproteína/metabolismo , Neoplasias Hepáticas/patología , Doxorrubicina/farmacología , Glicoconjugados/farmacologíaRESUMEN
A straightforward synthesis of carbohydrate templated isoxazolidines is described, by reaction of unprotected glycosylhydroxylamines (operating as 1,3-dipoles) with methyl acrylate using microwave activation. Rhamno- and erythro-isoxazolidines are recognized by plant cells, resulting in a strong ROS-production as a plant immune response, and exert a high antifungal activity against Botrytis cinerea.
Asunto(s)
Fungicidas Industriales , Antifúngicos/farmacología , Plantas , Glicoconjugados/farmacología , CarbohidratosRESUMEN
Glycoconjugate analogues in which the sp3 -hybridized C2 position of the carbohydrate structure (normally bearing a hydroxy group) is converted into a compact sp2 -hybridized exomethylene group are expected to have unique biological activities. We established ligand-controlled Tsuji-Trost-type glycosylation methodology to directly prepare a variety of these 2-exomethylene pseudo-glycoconjugates, including glucosylceramide analogues, in an α- or ß-selective manner. Glucocerebrosidase GBA1 cleaves these synthetic pseudo-ß-glucosylceramides similarly to native glucosylceramides. The pseudo-glucosylceramides exhibit selective ligand activity towards macrophage-inducible C-type lectin (Mincle), but unlike native glucosylceramides, are inactive towards CD1d.
Asunto(s)
Glucosilceramidas , Glicoconjugados , Ligandos , Glucosilceramidas/química , Glicoconjugados/farmacología , Glucosilceramidasa , GlicosilaciónRESUMEN
Polymer-based nanomaterials have exhibited promising alternative avenues to combat the globe challenge of multidrug-resistant bacterial infection. However, most of the reported polymeric nanomaterials have facially linear amphiphilic structures with positive net charges, which may lead to nonspecific binding, high hemolysis, and uncontrollable self-organization, limiting their practical applications. In this contribution, we report a one-dimensional glyconanorod (GNR) through self-assembly of well-defined ß-cyclodextrin-based glycoconjugates (RMan) featuring hydrophobic carbon-based chains and amide rhodamines with an adenosine triphosphate (ATP)-recognition site and targeted and hydrophilic mannoses and positively net-charged ethylene amine groups. The GNRs show superior targeting sensing and killing for Gram-negative Escherichia coli (E. coli) dominantly through the multivalent recognition between mannoses on the nanorod and the lectin on the surface of E. coli. Moreover, red fluorescence was light on due to the hydrogen bonding between amide rhodamine and ATP. Benefiting from the designs, the GNRs are capable of possessing a higher therapeutic index and of encapsulating other antibiotics. They exhibit an enhanced effect against E. coli strains. Intriguingly, the GNRs displayed a more reduced hemolysis effect and lower cytotoxicity compared to that of ethylene glyco-modified nanorods. These results reveal that the glyconanomaterials not only feature superior and targeted bacterial sensing and antibacterial activity, but also better biocompatibility compared with the widely used PEG-covered nanomaterials. Furthermore, the in vivo studies demonstrate that the targeted and ATP-responsive GNRs complexed with antibiotics showed better treatment using a mouse model of abdominal sepsis following intraperitoneal E. coli infection. The present work describes a targeted and effective sensing and antibacterial platform based on glycoconjugates that have potential applications for the treatment of infections caused by pathogenic microorganisms.
Asunto(s)
Escherichia coli , beta-Ciclodextrinas , Humanos , Hemólisis , Bacterias , Antibacterianos/farmacología , Antibacterianos/química , Glicoconjugados/farmacología , Glicoconjugados/química , beta-Ciclodextrinas/farmacologíaRESUMEN
Galectins are proteins of the family of human lectins. By binding terminal galactose units of cell surface glycans, they moderate biological and pathological processes such as cell signaling, cell adhesion, apoptosis, fibrosis, carcinogenesis, and metabolic disorders. The binding of monovalent glycans to galectins is usually relatively weak. Therefore, the presentation of carbohydrate ligands on multivalent scaffolds can efficiently increase and/or discriminate the affinity of the glycoconjugate to different galectins. A library of glycoclusters and glycodendrimers with various structural presentations of the common functionalized N-acetyllactosamine ligand was prepared to evaluate how the mode of presentation affects the affinity and selectivity to the two most abundant galectins, galectin-1 (Gal-1) and galectin-3 (Gal-3). In addition, the effect of a one- to two-unit carbohydrate spacer on the affinity of the glycoconjugates was determined. A new design of the biolayer interferometry (BLI) method with specific AVI-tagged constructs was used to determine the affinity to galectins, and compared with the gold-standard method of isothermal titration calorimetry (ITC). This study reveals new routes to low nanomolar glycoconjugate inhibitors of galectins of interest for biomedical research.
Asunto(s)
Galectinas , Glicoconjugados , Humanos , Ligandos , Galectinas/metabolismo , Glicoconjugados/farmacología , Glicoconjugados/química , Carbohidratos/química , Polisacáridos/metabolismoRESUMEN
Cancer, which is characterized by uncontrolled proliferation of abnormal cells, is a leading cause of morbidity and mortality worldwide. Cytotoxic chemotherapy, especially with platinum drugs, remains the mainstay of cancer treatment in the clinical setting. Despite phenomenal success, small-molecule chemotherapeutic drugs suffer from some serious drawbacks. Lack of cancer selectivity and the ensuing side effects mar the therapeutic potential of these drugs. Glycoconjugation has emerged as an attractive strategy for imparting selectivity and improving pharmacokinetics of cytotoxic agents. In this review, we provide an overview of the glycoconjugation strategy and then illustrate the application of this strategy with the help of some concrete examples of platinum based glycoconjugates. At the end we discuss a few important aspects of these glycoconjugates which merit further investigations.
Asunto(s)
Antineoplásicos , Neoplasias , Humanos , Platino (Metal) , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Neoplasias/tratamiento farmacológico , Sistemas de Liberación de Medicamentos , Glicoconjugados/farmacologíaRESUMEN
Acinetobacter baumannii is a opportunistic bacterial pathogen responsible for serious nosocomial infections that is becoming increasingly resistant against antibiotics. Capsular polysaccharides (CPS) that cover A. baumannii are a major virulence factor that play an important role in pathogenesis, are used to assign serotypes and provide the basis for vaccine development. Synthetic oligosaccharides resembling the CPS of A. baumannii 17978 were printed onto microarray slides and used to screen sera from patients infected with A. baumannii as well as a monoclonal mouse antibody (mAb C8). A synthetic oligosaccharide emerged from glycan array screening as lead for the development of a vaccine against A. baumannii 17978. Tetrasaccharide 20 is a key epitope for recognition by an antibody and is a vaccine lead.
Asunto(s)
Infecciones por Acinetobacter , Acinetobacter baumannii , Glicoconjugados , Vacunas Sintéticas , Infecciones por Acinetobacter/prevención & control , Acinetobacter baumannii/efectos de los fármacos , Animales , Antibacterianos/farmacología , Epítopos , Glicoconjugados/farmacología , Humanos , Ratones , Oligosacáridos , Polisacáridos , Vacunas Sintéticas/farmacología , Factores de VirulenciaRESUMEN
We have shown solvent- and substrate-dependent chiral inversion of a few glycoconjugate supramolecules. (Z)-F-Gluco, in which d-glucosamine has been attached chemically to Cbz-protected l-phenylalanine at the Câ terminus, forms a self-healing hydrogel through intertwining of the nanofibers wherein the gelators undergo lamellar packing in the ß-sheet secondary structures with a single chiral handedness. Dihybrid (Z)-F-gluco nanocomposite gel was prepared by in-situ formation of silver nanoparticles AgNPs in the gel; this enhances the mechanical properties of the composite gel through physical crosslinking without altering the packing pattern. In contrast, (Z)-L-gluco bearing an l-leucine moiety does not form a hydrogel but an organogel. Interestingly, the chiral handedness of the aggregates of (Z)-L-gluco can be reversed by choosing suitable solvents. In addition to self-healing behavior, (Z)-L-gluco gel revealed shape persistency. Further, (Z)-F-gluco hydrogel is benign, nontoxic, non-immunogenic, and non-allergenic in animal cells. AgNP-loaded (Z)-F-gluco hydrogel showed antibacterial activity against both Gram-positive and Gram-negative bacteria.
Asunto(s)
Antibacterianos , Nanopartículas del Metal , Animales , Antibacterianos/farmacología , Antibacterianos/química , Solventes/química , Plata/química , Nanopartículas del Metal/química , Bacterias Gramnegativas , Bacterias Grampositivas , Hidrogeles/química , Glicoconjugados/farmacologíaRESUMEN
New neutral carbene complexes of gold(I) [Au(Im-Me)X] (X = Cl, Au1; X = Br, Au2; X = I, Au3) have been synthesized and fully characterized by different techniques, including NMR and UV-vis absorption spectroscopy and single crystal X-ray diffraction. The carbene ligand Im-Me is decorated with a glucoside fragment via a triazole linker, obtainable through a click chemistry reaction. The compounds retain the Au-NHC fragment in aqueous solvents, and an equilibrium between the neutral halo- and the cationic di-carbene form [Au(Im-Me)2]+ is observed, whose extent follows the trend Au1 < Au2 < Au3. Cytotoxicity studies on two cancer and two non-tumorigenic cell lines reflect the solution behavior, as a certain difference among the complexes was disclosed, with the iodo complex Au3 being more active and selective. The compounds interact with both DNA and protein model systems. The X-ray structure of the adduct formed upon the reaction of Au1 with bovine pancreatic ribonuclease (RNase A) reveals Au binding at the side chain of His105 of both protein molecules A and B of the asymmetric unit. The binding of gold atoms at both the nitrogen atoms of the imidazole ring of His15 and at the N-terminal tail has been found in the adduct formed with hen egg white lysozyme.
Asunto(s)
ADN , Oro , Animales , Bovinos , Glicoconjugados/farmacología , Oro/química , Ligandos , Metano/análogos & derivados , Modelos MolecularesRESUMEN
Antimicrobial resistance (AMR) is emerging as the next potential pandemic. Different microorganisms, including the bacteria Acinetobacter baumannii, Clostridioides difficile, Escherichia coli, Enterococcus faecium, Klebsiella pneumoniae, Neisseria gonorrhoeae, Pseudomonas aeruginosa, non-typhoidal Salmonella, and Staphylococcus aureus, and the fungus Candida auris, have been identified by the WHO and CDC as urgent or serious AMR threats. Others, such as group A and B Streptococci, are classified as concerning threats. Glycoconjugate vaccines have been demonstrated to be an efficacious and cost-effective measure to combat infections against Haemophilus influenzae, Neisseria meningitis, Streptococcus pneumoniae, and, more recently, Salmonella typhi. Recent times have seen enormous progress in methodologies for the assembly of complex glycans and glycoconjugates, with developments in synthetic, chemoenzymatic, and glycoengineering methodologies. This review analyzes the advancement of glycoconjugate vaccines based on synthetic carbohydrates to improve existing vaccines and identify novel candidates to combat AMR. Through this literature survey we built an overview of structure-immunogenicity relationships from available data and identify gaps and areas for further research to better exploit the peculiar role of carbohydrates as vaccine targets and create the next generation of synthetic carbohydrate-based vaccines.
Asunto(s)
Antibacterianos , Farmacorresistencia Bacteriana , Antibacterianos/farmacología , Glicoconjugados/farmacología , Polisacáridos , Carbohidratos , Vacunas SintéticasRESUMEN
The biomedical application of corannulene π-bowls is historically limited by low solubility and bioavailability despite the potential in their unique electronic properties for new functional materials. Herein, the unexpected role and molecular mechanism of Corranulene π-bowls are uncovered in biomedical applications as an effective anticancer agent for Warburg effect mediated selective tumor targeting. The corannulene triazolyl monosaccharides Cor-sugars exhibit highly potent cytotoxicity against human cancer cells and effectively inhibit xenograft growth of hyperglycolytic tumors. Particularly, the galactose-conjugated Cor-gal exhibits superior in vivo anticancer efficacy in A549 tumor models with outstanding safety profile compared to doxorubicin. Moreover, the combined treatment of Cor-gal with immune checkpoint inhibitor results in an effective synergy in treating H460 human lung carcinoma. An uptake mechanism study reveals that Cor-sugars exploit tumor-specific glucose transporter glucose transporter 1 (GLUT1) for targeted cell delivery and intra-tumoral accumulation through the cancer-specific Warburg effect. Their significant anticancer activity is attributed to multiphasic DNA-binding and cell cycle alteration effects. This study uncovers new molecular properties of corannulene buckybowl and enabling their potential new applications in biomedical engineering.
Asunto(s)
Antineoplásicos , Neoplasias , Hidrocarburos Policíclicos Aromáticos , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Línea Celular Tumoral , Glicoconjugados/química , Glicoconjugados/farmacología , Humanos , Neoplasias/tratamiento farmacológicoRESUMEN
A series of new colchicine glycoconjugates as tubulin polymerization inhibitors were designed by targeting strategy based on Warburg effect. All of the colchicine glycoconjugates were synthesized and then evaluated for their antiproliferative activities against three human cancer lines HT-29, MCF-7 and Hep-3B. Among them, 1e exhibited greater than 10 times selectivity between GLUT1 highly expressed cells (HT-29 and MCF-7) and GLUT1 lowly expressed cells (Hep-3B), and also showed lower cytotoxicity against HUVECs compared with colchicine. Moreover, 1e significantly inhibited tubulin polymerization and disrupted microtubule networks. GLUT1 inhibitor-dependent cytotoxicity assay demonstrated that the uptake of 1e was regulated via GLUT1. Molecular docking studies showed that 1e could be a substrate of GLUT1 and bind to the colchicine site of tubulin.
Asunto(s)
Antineoplásicos/farmacología , Colchicina/farmacología , Diseño de Fármacos , Glicoconjugados/farmacología , Moduladores de Tubulina/farmacología , Tubulina (Proteína)/metabolismo , Antineoplásicos/síntesis química , Antineoplásicos/química , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Colchicina/química , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Glicoconjugados/síntesis química , Glicoconjugados/química , Humanos , Simulación del Acoplamiento Molecular , Estructura Molecular , Polimerizacion/efectos de los fármacos , Relación Estructura-Actividad , Moduladores de Tubulina/síntesis química , Moduladores de Tubulina/químicaRESUMEN
The design of prodrugs is one of the important strategies for selective anti-cancer therapies. When designing prodrugs, attention is paid to the possibility of their targeting tumor-specific markers such as proteins responsible for glucose uptake. That is why glycoconjugation of biologically active compounds is a frequently used strategy. Glycoconjugates consisting of three basic building blocks: a sugar unit, a linker containing a 1,2,3-triazole ring, and an 8-hydroxyquinoline fragment was described earlier. It is not known whether their cytotoxicity is due to whole glycoconjugates action or their metabolites. To check the biological activity of products that can be released from glycoconjugates under the action of hydrolytic enzymes, the synthetically obtained potential metabolites were tested in vitro for the inhibition of proliferation of HCT-116, MCF-7, and NHDF-Neo cell lines using the MTT assay. Research shows that for the full activity of glycoconjugates, the presence of all three building blocks in the structure of a potential drug is necessary. For selected derivatives, additional tests of targeted drug delivery to tumor cells were carried out using polymer nanocarriers in which they are encapsulated. This approach significantly lowered the determined IC50 values of the tested compounds and improved their selectivity and effectiveness.
Asunto(s)
Antineoplásicos/farmacología , Glicoconjugados/farmacología , Profármacos/farmacología , Quinolinas/farmacología , Antineoplásicos/síntesis química , Antineoplásicos/química , Antineoplásicos/metabolismo , Apoptosis/efectos de los fármacos , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Ensayos de Selección de Medicamentos Antitumorales , Glicoconjugados/síntesis química , Glicoconjugados/química , Glicoconjugados/metabolismo , Humanos , Células MCF-7 , Neoplasias/tratamiento farmacológico , Neoplasias/metabolismo , Profármacos/síntesis química , Profármacos/química , Profármacos/metabolismo , Quinolinas/síntesis química , Quinolinas/química , Quinolinas/metabolismo , Relación Estructura-ActividadRESUMEN
Extraintestinal pathogenic Escherichia coli O1 is a frequently identified serotype that causes serious infections and is often refractory to antimicrobial therapy. Glycoconjugate vaccine represents a promising measure to reduce ExPEC infections. Herein, we designed an O1-specific glyco-optimized chassis strain for manufacture of O-polysaccharide (OPS) antigen and OPS-based bioconjugate. Specifically, OPS and OPS-based glycoprotein were synthesized in glyco-optimized chassis strain, when compared to the unmeasurable level of the parent strain. The optimal expression of oligosaccharyltransferase and carrier protein further improved the titer. MS analysis elucidated the correct structure of resulting bioconjugate at routine and unreported glycosylation sequons of carrier protein, with a higher glycosylation efficiency. Finally, purified bioconjugate stimulated mouse to generate specific IgG antibodies and protected them against virulent ExPEC O1 challenge. The plug-and-play glyco-optimized platform is suitable for bioconjugate synthesis, thus providing a potential platform for future medical applications.
Asunto(s)
Antibacterianos/farmacología , Escherichia coli Patógena Extraintestinal/efectos de los fármacos , Glicoconjugados/farmacología , Polisacáridos/farmacología , Ingeniería de Proteínas , Vacunas Conjugadas/farmacología , Animales , Antibacterianos/síntesis química , Antibacterianos/química , Desarrollo de Medicamentos , Femenino , Glicoconjugados/síntesis química , Glicoconjugados/química , Ratones , Pruebas de Sensibilidad Microbiana , Polisacáridos/síntesis química , Polisacáridos/química , Vacunas Conjugadas/químicaRESUMEN
Tacrine is a known Acetylcholinesterase (AChE) inhibitors having hepatotoxicity as main liability associated with it. The present study aims to reduce its hepatotoxicity by synthesizing tacrine linked triazole glycoconjugates via Huisgen's [3 + 2] cycloaddition of anomeric azides and terminal acetylenes derived from tacrine. A series of triazole based glycoconjugates containing both acetylated (A-1 to A-7) and free sugar hydroxyl groups (A-8 to A-14) at the amino position of tacrine were synthesized in good yield taking aid from molecular docking studies and evaluated for their in vitro AChE inhibition activity as well as hepatotoxicity. All the hybrids were found to be non-toxic on HePG2 cell line at 200 µM (100 % cell viability) as compared to tacrine (35 % cell viability) after 24 h of incubation period. Enzyme kinetic studies carried out for one of the potent hybrids in the series A-1 (IC50 0.4 µM) revealed its mixed inhibition approach. Thus, compound A-1 can be used as principle template to further explore the mechanism of action of different targets involved in Alzheimer's disease (AD) which stands as an adequate chemical probe to be launched in an AD drug discovery program.
Asunto(s)
Acetilcolinesterasa/metabolismo , Antineoplásicos/farmacología , Inhibidores de la Colinesterasa/farmacología , Diseño de Fármacos , Glicoconjugados/farmacología , Tacrina/farmacología , Triazoles/farmacología , Antineoplásicos/síntesis química , Antineoplásicos/química , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Inhibidores de la Colinesterasa/síntesis química , Inhibidores de la Colinesterasa/química , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Glicoconjugados/química , Células Hep G2 , Humanos , Estructura Molecular , Relación Estructura-Actividad , Tacrina/química , Triazoles/químicaRESUMEN
In addition to a variety of viral-glycoprotein receptors (e.g., heparan sulfate, Niemann-Pick C1, etc.), dendritic cell-specific intercellular adhesion molecule-3-grabbing nonintegrin (DC-SIGN), from the C-type lectin receptor family, plays one of the most important pathogenic functions for a wide range of viruses (e.g., Ebola, human cytomegalovirus (HCMV), HIV-1, severe acute respiratory syndrome coronavirus 2, etc.) that invade host cells before replication; thus, its inhibition represents a relevant extracellular antiviral therapy. We report two novel p-tBu-calixarene glycoclusters 1 and 2, bearing tetrahydroxamic acid groups, which exhibit micromolar inhibition of soluble DC-SIGN binding and provide nanomolar IC50 inhibition of both DC-SIGN-dependent Jurkat cis-cell infection by viral particle pseudotyped with Ebola virus glycoprotein and the HCMV-gB-recombinant glycoprotein interaction with monocyte-derived dendritic cells expressing DC-SIGN. A unique cooperative involvement of sugar, linker, and calixarene core is likely behind the strong avidity of DC-SIGN for these low-valent systems. We claim herein new promising candidates for the rational development of a large spectrum of antiviral therapeutics.
Asunto(s)
Calixarenos/química , Moléculas de Adhesión Celular/antagonistas & inhibidores , Glicoconjugados/metabolismo , Glicoproteínas/antagonistas & inhibidores , Ácidos Hidroxámicos/química , Lectinas Tipo C/antagonistas & inhibidores , Fenoles/química , Receptores de Superficie Celular/antagonistas & inhibidores , Proteínas Virales/antagonistas & inhibidores , Antivirales/química , Antivirales/metabolismo , Antivirales/farmacología , Moléculas de Adhesión Celular/metabolismo , Línea Celular , Citomegalovirus/metabolismo , Células Dendríticas/citología , Células Dendríticas/metabolismo , Ebolavirus/fisiología , Glicoconjugados/química , Glicoconjugados/farmacología , Glicoproteínas/genética , Glicoproteínas/metabolismo , Humanos , Células Jurkat , Lectinas Tipo C/metabolismo , Modelos Biológicos , Unión Proteica , Receptores de Superficie Celular/metabolismo , Proteínas Recombinantes/biosíntesis , Proteínas Recombinantes/química , Proteínas Recombinantes/aislamiento & purificación , Proteínas Virales/genética , Proteínas Virales/metabolismoRESUMEN
The heterotrimeric Sec61 complex is a major site for the biogenesis of transmembrane proteins (TMPs), accepting nascent TMP precursors that are targeted to the endoplasmic reticulum (ER) by the signal recognition particle (SRP). Unlike most single-spanning membrane proteins, the integration of type III TMPs is completely resistant to small molecule inhibitors of the Sec61 translocon. Using siRNA-mediated depletion of specific ER components, in combination with the potent Sec61 inhibitor ipomoeassin F (Ipom-F), we show that type III TMPs utilise a distinct pathway for membrane integration at the ER. Hence, following SRP-mediated delivery to the ER, type III TMPs can uniquely access the membrane insertase activity of the ER membrane complex (EMC) via a mechanism that is facilitated by the Sec61 translocon. This alternative EMC-mediated insertion pathway allows type III TMPs to bypass the Ipom-F-mediated blockade of membrane integration that is seen with obligate Sec61 clients.
Asunto(s)
Retículo Endoplásmico/metabolismo , Membranas Intracelulares/metabolismo , Proteínas de la Membrana/metabolismo , Biosíntesis de Proteínas , Canales de Translocación SEC/metabolismo , Animales , Retículo Endoplásmico/efectos de los fármacos , Glicoconjugados/farmacología , Células HeLa , Humanos , Immunoblotting , Membranas Intracelulares/efectos de los fármacos , Modelos Biológicos , Transporte de Proteínas/efectos de los fármacos , Interferencia de ARN , Canales de Translocación SEC/genética , Partícula de Reconocimiento de Señal/metabolismoRESUMEN
The C-type lectin receptor DC-SIGN mediates interactions with envelope glycoproteins of many viruses such as SARS-CoV-2, ebola, and HIV and contributes to virus internalization and dissemination. In the context of the recent SARS-CoV-2 pandemic, involvement of DC-SIGN has been linked to severe cases of COVID-19. Inhibition of the interaction between DC-SIGN and viral glycoproteins has the potential to generate broad spectrum antiviral agents. Here, we demonstrate that mannose-functionalized poly-l-lysine glycoconjugates efficiently inhibit the attachment of viral glycoproteins to DC-SIGN-presenting cells with picomolar affinity. Treatment of these cells leads to prolonged receptor internalization and inhibition of virus binding for up to 6â h. Furthermore, the polymers are fully bio-compatible and readily cleared by target cells. The thermodynamic analysis of the multivalent interactions reveals enhanced enthalpy-driven affinities and promising perspectives for the future development of multivalent therapeutics.