Neuromyelitis optica (NMO) is an inflammatory demyelinating disease of the central nervous system in which binding of pathogenic autoantibodies (NMO-IgG) to astrocyte aquaporin-4 (AQP4) cause complement-dependent cytotoxicity (CDC) and inflammation. We previously reported a wide range of binding affinities of NMO-IgGs to AQP4 in separate tetramers versus intramembrane aggregates (orthogonal ...

Neuromyelitis optica (NMO) is an inflammatory demyelinating disease of spinal cord and optic nerve caused by pathogenic autoantibodies (NMO-IgG) against astrocyte aquaporin-4 (AQP4). We developed a high-throughput screen to identify blockers of NMO-IgG binding to human AQP4 using a human recombinant monoclonal NMO-IgG and transfected Fisher rat thyroid cells stably ...

Protease-activated receptor 1 (PAR1) is an unusual GPCR that interacts with multiple G protein subfamilies (G(q/11), G(i/o), and G(12/13)) and their linked signaling pathways to regulate a broad range of pathophysiological processes. However, the molecular mechanisms whereby PAR1 interacts with multiple G proteins are not well understood. Whether PAR1 interacts ...

Synergy between Cellulomonas flavigena xylanase CflXyn11A and Trichoderma reesei endoglucanase TrCel7B was assessed during hydrolysis of alkaline pretreated sugar cane bagasse (SCB) after 12-48h, applying the individual enzymes and mixtures of the enzymes. A high degree of synergy (6.3) between CflXyn11A and TrCel7B in hydrolysis of SCB was observed after ...

When reaching the zona pellucida (ZP) of the oocyte, spermatozoa apply propulsive forces produced by the motion of their flagella, which push against the ZP and theoretically should contribute to their penetration into the ZP. Additionally, specific receptors on the spermatozoon head bind to ZP3 ligands located on the surface ...

JC virus (JCV) is the etiological agent of the demyelinating disease Progressive Multifocal Leukoencephalopathy, an AIDS defining illness and serious complication of monoclonal antibody therapies. Initial infection likely occurs in childhood. In the working model of dissemination, virus persists in the kidney and lymphoid tissues until immune suppression/modulation causes reactivation ...

Type II phosphatidylinositol (PtdIns) 4-kinases produce PtdIns 4-phosphate, an early key signaling molecule in phosphatidylinositol cycle, which is indispensable for T cell activation. Type II PtdIns 4-kinase alpha and beta have similar biochemical properties. To distinguish these isoforms Epigallocatechin gallate (EGCG) has been evaluated as a specific inhibitor. EGCG is ...

We analyzed the nonlinear current-voltage relationships of the early conducting state of channelrhodopsin-2 expressed in Xenopus oocytes and human embryonic kidney cells with respect to changes of the electrochemical gradients of H(+), Na(+)/K(+), and Ca(2+)/Mg(2+). Several models were tested for wild-type ChR2 and mutations at positions E90, E123, H134, and ...

Interactions between the posterior parietal cortex and the early visual cortex have been proposed to play a central role in the binding of visual features into coherent objects. Here we investigated the importance of these interactions by contrasting the time windows at which the early visual cortex (V1/V2) and the ...

SARA, an early endosomal protein, plays a key role in TGFβ signalling, as it presents SMAD2 and SMAD3 for phosphorylation by the activated TGFβ receptors. Here, we show that ERBIN is a new SARA-interacting protein that can be recruited by SARA to early endosomes. ERBIN was recently shown to bind ...

Although small molecules that modulate amyloid formation in vitro have been identified, significant challenges remain in determining precisely how these species act. Here we describe the identification of rifamycin SV as a potent inhibitor of β(2) microglobulin (β(2)m) fibrillogenesis when added during the lag time of assembly or early during ...

The equine herpesvirus 1 (EHV-1) negative regulatory IR2 protein (IR2P), an early 1,165-amino acid (aa) truncated form of the 1487-aa immediate-early protein (IEP), lacks the trans-activation domain essential for IEP activation functions but retains domains for binding DNA, TFIIB, and TBP and the nuclear localization signal. IR2P mutants of the ...

Eukaryotic initiation factor eIF4E performs a key early step in translation by specifically recognizing the m(7)GpppN cap structure at the 5' end of cellular mRNAs. Many viral mRNAs lack a 5' cap and thus bypass eIF4E. In contrast, we reported a cap-independent translation element (PTE) in Pea enation mosaic virus ...

Diphtheria toxin has been well characterized in terms of its receptor binding and receptor mediated endocytosis. However, the precise mechanism of the cytosolic release of diphtheria toxin fragment A from early endosomes is still unclear. Various reports differ regarding the requirement for cytosolic factors in this process. Here, we present ...

Many early drug research efforts are too reductionist thereby not delivering key parameters such as kinetics and thermodynamics of target-ligand binding. A set of human D-Amino Acid Oxidase (DAAO) inhibitors 1-6 was applied to demonstrate the impact of key biophysical techniques and physicochemical methods in the differentiation of chemical entities ...

Human germinal center associated lymphoma (HGAL) is a germinal center-specific gene whose expression correlates with a favorable prognosis in patients with diffuse large B-cell and classic Hodgkin lymphomas. HGAL is involved in negative regulation of lymphocyte motility. The movement of lymphocytes is directly driven by actin polymerization and actin-myosin interactions. ...

The cleavage factor I(m) (CF I(m)), consists of a 25 kDa subunit (CF I(m)25) and one of three larger subunits (CF I(m)59, CF I(m)68, CF I(m)72), and is an essential protein complex for pre-mRNA 3'-end cleavage and polyadenylation. It recognizes the upstream sequence of the poly(A) site in a sequence-dependent ...

This short review summarizes the localization and effects of the plant lectin soybean agglutinin (SBA) on the injured and non-injured organ-cultured rat corneal endothelium. Although the tissue exists as a non-cycling monolayer on the posterior corneal surface a circular freeze injury promotes wound repair as cells initiate DNA synthesis, mitosis ...

RNA-binding proteins mediate the function of all RNAs. Since few distinct RNA-binding domains (RBDs) exist, with most RBDs contacting only a few nucleotides, RNA-binding proteins often combine multiple RNA-binding motifs to achieve a higher affinity and selectivity for their targets. Rrp5, a ribosome assembly factor essential for both 40S and ...

A brief historical introduction describes early attempts to silence specific genes using the antisense oligonucleotides that flourished in the 1980s. Early aspirations for therapeutic applications were almost extinguished by the unexpected complexity of oligonucleotide pharmacology. Once the biochemistry and molecular biology behind some of the pharmacology was worked out, new ...

Transcription of ribosome RNA precursor (pre-rRNA) and pre-rRNA processing are coordinated by a subset of U three proteins (UTPs) known as transcriptional UTPs (t-UTPs), which participate in pre-rRNA transcription in addition to participation in 18 S rRNA processing. However, the mechanism by which t-UTPs function in pre-rRNA transcription remains undetermined. ...

The timely nuclear-cytoplasmic translocation of proteins and RNAs by importins and exportins is important for controlling biological processes. Since the 2004 publication of the first exportin structure, Cse1p, the X-ray structures of exportin-5 complexed with pre-microRNA, exportin-t complexed with tRNA, and three CRM1-related structures have revealed the binding mechanism involved ...

Versatile synthesis of fluorescent, carbohydrate-functionalized oligothiophene hybrids via Sonogashira-type cross coupling reactions is reported. The mannose derivatives reveal specific binding with the model lectin from Canavalia enisformis (Concanavalin A).

The interaction of trimannoside, α-benzyl 3, 6-di-O-(α-D-mannopyranosyl)-α-D-mannopyranoside, 1 with ASAI (Allium sativam agglutinin I, garlic lectin) was studied to reveal the conformational preferences of this ligand in bound-state and detailed binding mode at atomic level. The binding phenomenon was then compared with another well-known mannose-binding lectin, ConA (Concanavalin A). Structural ...

We report the synthesis and characterization of multivalent mannose conjugates based on high molecular weight hyperbranched polyglycerols (HPG). A range of glycoconjugates were synthesized from high molecular weight HPGs (up to 493 kDa) and varying mannose units (22-303 per HPG). Hemagglutination assays using fresh human red blood cells and concanavalin ...

Gold nanoparticles stabilized with thioglucose (TGlu-AuNPs), which have carboxyl groups on the particle surface as anchoring sites for covalent immobilization of biomolecules, were prepared by the chemical reduction of HAuCl4 using 1-thio-β-D-glucose as a reducing and stabilizing agent, and their application to colorimetric bioassay was demonstrated using the carbohydrate-lectin system. ...

In photodynamic therapy, the specificity of a photosensitizer and its penetration into tumor cells are crucial. We have analyzed the ability of newly synthesized meso-(tetraphenyl)porphyrins to be recognized by a model of mannose-specific proteins overexpressed at the surface of retinoblastoma cells. The specific interaction of porphyrin with Con A was ...

For the GalNAcalpha1--> specific Agaricus bisporus agglutinin (ABA) from an edible mushroom, the mechanism of polyvalent Galbeta1-->3/4GlcNAcbeta1--> complex in ABA-carbohydrate recognition has not been well defined since Gal and GlcNAc are weak ligands. By enzyme-linked lectinosorbent and inhibition assays, we show that the polyvalent Galbeta1-->3/4GlcNAcbeta1--> in natural glycans also play ...

The inhibition of carbohydrate-protein interactions by tailored multivalent ligands is a powerful strategy for the treatment of many human diseases. Crucial for the success of this approach is an understanding of the molecular mechanisms as to how a binding enhancement of a multivalent ligand is achieved. We have synthesized a ...

The synthesis of mannose-substituted tetraphenylethenes (TPEs) and their aggregation-induced emission (AIE) behavior, induced by interactions with concanavalin A (Con A), are reported. A mixture of the mannose-TPE conjugates and Con A in a buffer solution displays an intense blue emission on agglutination within a few seconds, which serves as a ...

Two types of nonspacer- and spacer-N-linked tetravalent glycosides bearing N-acetylglucosamine (GlcNAc), N,N'-diacetylchitobiose [(GlcNAc)(2)] and N-acetyllactosamine (LacNAc) were designed and prepared as glycomimetics. The interactions of wheat germ (Triticum vulgaris) agglutinin (WGA) and coral tree (Erythrina cristagalli) agglutinin (ECA) with a series of tetravalent glycosides and related compounds were studied using ...

The lectin-binding pattern was compared in the normal and pathological uterus of sows during the ovarian cycle. The following biotinylated lectins were used: Con A, DBA, SBA, PNA, RCA-I, UEA-I and WGA. Glycoconjugate labelling showed differences between phases of ovarian cycle and presence of morphologic lesions. Cystic endometrial hyperplasia increased ...

Piwi proteins such as Drosophila Aubergine (Aub) and mouse Miwi are essential for germline development and for primordial germ cell (PGC) specification. They bind piRNAs and contain symmetrically dimethylated arginines (sDMAs), catalyzed by dPRMT5. PGC specification in Drosophila requires maternal inheritance of cytoplasmic factors, including Aub, dPRMT5, and Tudor (Tud), ...

Focused on the natural biodegradable material of chitosan (CS), this investigation concerned its spray-dried nanoparticles-in-microparticles (NiMPs) modified with ulex europaeus agglutinin (UEA). Chitosan nanoparticles were obtained by ionotropic gelation process with pentasodium tripolyphosphate as gelatinizer. Then UEA lectin was bound onto the CS nanoparticles activated by glutaraldehyde. The conjugated spherical ...

A biotinylated mannotriose (Man3-bio) was dispersively immobilized in the matrix of biotinylated lactose (Gal-Glc-bio) on a streptavidin-covered, 27-MHz quartz crystal microbalance (QCM), and binding kinetics of concanavalin A (Con A) to Man3-bio in the Gal-Glc-bio matrix could be obtained from frequency decreases (mass increases) of the QCM. Association constants (K(a)) ...

An electrochemical method that uses glucose labeled with an electroactive compound was developed to evaluate the binding of wheat germ agglutinin (WGA) to cellohexose-modified magnetic microbeads. Cellohexose was attached to amino groups on the magnetic bead surface via formation of a Schiff's base. The labeled glucose acts as an electrochemical ...

Glycoanalysis is important in the manufacture and quality control of protein therapeutics. An emerging method for glycoanalysis is the use of lectin arrays. Critical to the performance of these arrays is the immobilization of lectin molecules. Polydopamine has recently been shown to adsorb to a wide variety of surfaces. In ...

We have designed and synthesized ruthenium complexes bearing clustered galactose Ru(bpy-2Gal)(3) and glucose Ru(bpy-2Glc)(3). Changes in fluorescence emission (FE) and fluorescence polarization (FP) of the metalloglycoclusters were measured by adding each lectin (peanut agglutinin (PNA), Ricinus communis agglutinin 120 (RCA), concanavalin A (ConA), or wheat germ agglutinin (WGA)) or tetanus ...

alpha-D-Mannopyranosyl units were attached to an aromatic scaffold through disulfide linkages to obtain mono- to trivalent glycosylated ligands for lectin binding studies. Isothermal titration calorimetric (ITC) measurements indicated that binding affinities of these derivatives to Concanavalin A (Con A) were comparable to or slightly higher than that of methyl alpha-D-mannopyranoside ...

Peptide-nucleic acids (PNAs) including pyrimido[4,5-d]pyrimidine-2,4,5,7-(1H,3H,6H,8H)-tetraone (PPT) as a nucleobase were synthesized, and their binding affinity for the complementary oligodeoxyribonucleotides was investigated. We found that PNAs with one or two PPT(s) and natural nucleobases (i.e., adenine, cytosine, guanine, or thymine) have excellent binding affinity for oligodeoxyribonucleotides with complementary bases at the ...

Equine cumulus-oocyte complexes (COCs) were analyzed by means of 13 lectins to evaluate their glycoconjugate patterns and to verify differences between COCs recovered with compact (Cp) and expanded (Exp) cumulus. Cumulus cells showed a similar staining pattern in both Cp and Exp COCs with all lectins used, except for a ...

A facile synthesis of cyclopeptide-centered multivalent glycoclusters using Cu(I) catalyzed Huisgen 1,3-dipolar cycloaddition of azides and terminal alkynes, so called 'click chemistry', has been developed. The affinities of mannose-specific protein Concanavalin A (Con A) toward two synthetic glycoclusters respectively bearing divalent or tetravalent mannoses were investigated by surface plasmon resonance ...

The distribution of lectin bindings in the testis of the smallest ruminant, lesser mouse deer (Tragulus javanicus), was studied using 12 biotinylated lectins specific for d-galactose (peanut agglutinin PNA, Ricinus communis agglutinin RCA I), N-acetyl-d-galactosamine (Dolichos biflorus agglutinin DBA, Vicia villosa agglutinin VVA, Soybean agglutinin SBA), N-acetyl-D-glucosamine and sialic acid ...

Carbohydrate-protein interactions govern many crucial life processes involved in cell recognition events, but are often difficult to study because the interactions are weak, and multivalent exposure appears to be crucial for their biological function. We have used self-assembled monolayers (SAMs) of neoglycoconjugates as a model system to probe the specific ...

AIMS: To assess in vitro the ability of some dairy bacteria to bind concanavalin A (Con A), peanut agglutinin (PNA) and jacalin (AIL), preventing their toxicity on mouse intestinal epithelial cells (IEC). METHODS AND RESULTS: Con A and AIL reduced significantly IEC viability in vitro, as determined by Trypan Blue ...

A strategy involving the conjugation of fluorescent quantum dot (QD) with wheat germ agglutinin (WGA) acting as fluorescent and topographic probes prior to cell surface staining is developed for fluorescence microscopy and atomic force microscopy (AFM). This strategy provided at least two advantages: (a) an amplified fluorescence of WGA-QD aggregates, ...

Surface plasmon resonance (SPR) was used to screen the interaction between a variety of affinity ligands and hemagglutinin (HA) from human influenza virus, with the aim of identifying low affinity ligands useful for the development of a rapid bioanalytical sensor. Three sialic acid-based structures and four lectins were evaluated as ...

Lectin-immobilized fluorescent nanospheres were designed with the aim of developing a novel endoscopic imaging agent for the detection of early colorectal cancer. Submicron-sized polystyrene nanospheres with surface poly(N-vinylacetamide) (PNVA) and poly(methacrylic acid) (PMAA) chains encapsulating fluorescein-labeled cholesterol were prepared as a platform of the imaging agent. Peanut agglutinin (PNA) was ...

The binding between glucose residues and wheat germ agglutinin (WGA) on thionine/glucose-modified magnetic microbeads was evaluated using voltammetry. Thionine is an electroactive compound and has two amino groups. Thionine was immobilized to magnetic beads via cross-linking of the amino groups on the beads with an amino group on thionine. Glucose ...

The voltammetric behavior of wheat-germ agglutinin (WGA) on a chitin-modified carbon-paste electrode (CPE) was investigated using glucose labeled with an electroactive compound. WGA usually consists of two subunits, each with two binding sites for sugars. WGA was immobilized on the electrode surface by selective binding to a N-acetylglucosamine residue of ...