A5042984364- Glycosylation and Glycoproteins Research
- Carbohydrate Chemistry and Synthesis
- Antimicrobial Peptides and Activities
- Monoclonal and Polyclonal Antibodies Research
- Biochemical and Structural Characterization
- RNA and protein synthesis mechanisms
- Enzyme Production and Characterization
- Chemical Synthesis and Analysis
- Enzyme Structure and Function
- Bacteriophages and microbial interactions
- Insect and Pesticide Research
- Peptidase Inhibition and Analysis
- Immune Response and Inflammation
- Coccidia and coccidiosis research
- Phytochemical compounds biological activities
- Galectins and Cancer Biology
- Microbial Natural Products and Biosynthesis
- Biochemical and Molecular Research
- Protein Structure and Dynamics
- Phytochemistry and Bioactive Compounds
- Natural product bioactivities and synthesis
- Amoebic Infections and Treatments
- Protein Degradation and Inhibitors
- Heme Oxygenase-1 and Carbon Monoxide
- NF-κB Signaling Pathways
National Institute of Immunology
2013-2023
University of Hyderabad
2005
University of Alberta
1990-1994
Southern Methodist University
1994
University of Lucknow
1985-1988
Abstract The glycosyltransferases controlling the biosynthesis of cell-surface complex carbohydrates transfer glycosyl residues from sugar nucleotides to specific hydroxyl groups acceptor oligosaccharides. These enzymes represent prime targets for design glycosylation inhibitors with potential specifically alter structures glycoconjugates. With aim producing such inhibitors, synthetic oligosaccharide substrates were prepared eight different glycosyltransferases. investigated were: A,...
Abstract The proline-rich antimicrobial peptide (PrAMP) drosocin is produced by Drosophila species to combat bacterial infection. Unlike many PrAMPs, O-glycosylated at threonine 11, a post-translation modification that enhances its activity. Here we demonstrate the O-glycosylation not only influences cellular uptake of but also interacts with intracellular target, ribosome. Cryogenic electron microscopy structures glycosylated on ribosome 2.0–2.8-Å resolution reveal interferes translation...
The Lewis alpha (1-->3/4)-fucosyltransferase (Le-FucT) is known to fucosylate both Type I (beta Gal(1-->3) beta GlcNAc) and II Gal(1-->4) sequences even when these are sialylated at OH-3 or fucosylated OH-2 of the terminal Gal residues. These acceptor ubiquitous on mammalian cell-surface glycoproteins glycolipids. Le-FucT enzyme therefore a potential candidate as universal reagent for modification cell surfaces. We have found that readily accessible, partially purified from human milk, which...
Baby hamster kidney (BHK) cells transformed with Rous sarcoma virus, RS-BHK cells, demonstrate a 2.5-fold increase in the activity of N-acetylglucosaminyltransferase V (GlcNAc-T V, EC 2.4.1.155), and this appears to be specific for enzyme. By contrast, lectin-resistant BHK cell line selected its ability grow high levels L-phytohemagglutinin, LP3.3, is characterized by decrease GlcNAc-T activity. To test if these alterations apparent Vmax are due changes efficiency populations enzymes LP3.3...
The following study examines the calmodulin (CaM) branch of calcium signal pathway in protozoan parasite Trypanosoma brucei. To accomplish this goal, a subset cytosolic CaM-binding proteins (CaMBPs) was partially purified by combination DE52 and CaM-Sepharose affinity chromatography. Monoclonal antibodies (CBP-KK1) were used to clone cDNA for 53-kDa CaMBP from lambda ZAP expression library metacyclic stage T. deduced amino acid sequence CaMBP-12B had 81% overall identity translation...
The shared surface topology of two chemically dissimilar but functionally equivalent molecular structures has been analyzed. A carbohydrate moiety (α-D-mannopyranoside) and a peptide molecule (DVFYPYPYASGS) bind to concanavalin at common binding site. cross-reactivity the polyclonal antibodies (pAbs) was used for understanding topological relationship between these independent ligands. anti-α-D-mannopyranoside pAbs recognized various ligands A, anti-DVFYPYPYASGS ligands, providing direct...
Abstract The comparative analysis of two cationic antibacterial peptides the cathelicidin family—indolicidin and tritrypticin—enabled addressing structural features critical for mechanism indolicidin activity. Functional behavior retro‐indolicidin was found to be identical that native indolicidin. It is apparent gross conformational propensities associated with retro‐peptides resemble those sequences, suggesting can have similar structures. Both show affinities while binding endotoxin,...
Abstract Molecular mimicry manifests antagonistically with respect to the specificity of immune recognition. However, it often occurs because different Ags share surface topologies in terms shape or chemical nature. It also when a flexible paratope accommodates dissimilar by adjusting structural features according antigenic epitopes differential positioning Ag combining site. Toward deciphering basis molecular mimicry, mAb 2D10 was isolated from maturing response elicited against methyl...
The extraordinary recognition specificity of lectins for carbohydrate ligands appears to be violated as they also bind porphyrins and other noncarbohydrate ligands. In this study, crystal structures meso-tetrasulfonatophenylporphyrin (H2TPPS) bound peanut agglutinin (PNA) in the presence absence lactose were determined. binding H2TPPS with PNA involved 11 molecules different supramolecular stacking arrangements associated a tetramer crystals PNA−H2TPPS binary complex well PNA−H2TPPS−lactose...
The crystal structure of the complex meso-tetrasulfonatophenylporphyrin (H2TPPS) with jack fruit (Artocarpus integriflora) agglutinin (jacalin) has been determined at 1.8 Å resolution. A porphyrin pair is sandwiched between two symmetry-related jacalin monomers in crystal, leading to a cross-linking network protein molecules. Apart from stacking interactions, H2TPPS also forms hydrogen bonds, some involving water bridges, carbohydrate-binding site. residues that are involved rendering...
Abstract Structural and physiological facets of carbohydrate-peptide mimicry were addressed by analyzing the Ab response to α-d-mannopyranoside. mAbs against α-d-mannopyranoside generated screened with carbohydrate-mimicking 12 mer (DVFYPYPYASGS) peptide. Three mAbs, 2D10, 1H11, 1H7, which subjected detailed analysis, exhibit diverse V gene usage, indicating their independent germline origins. Although mAb 1H7 was specific in binding only immunizing Ag, Abs 2D10 1H11 recognize peptide as...
Abstract Retro-inverso (ri) analogs of model T cell and B epitopes were predictively designed as mimics then assayed for activity to understand the basis functional ri-antigenic peptide mimicry. ri versions two MHC class I binding epitopes, one from a vesicular stomatitis virus glycoprotein (VSVp) another OVA (OVAp), exhibit structural well mimicry their native counterparts. The peptides conformational plasticity they bind (H-2Kb) similar counterparts both in silico vivo. In fact, ri-OVAp is...
Entamoeba histolytica, an early branching eukaryote, is the etiologic agent of amebiasis. Calcium plays a pivotal role in pathogenesis amebiasis by modulating cytopathic properties parasite. However, mechanistic Ca2+ and calcium-binding proteins E. histolytica remains poorly understood. We had previously characterized novel protein (EhCaBP1) from histolytica. Here, we report identification partial characterization isoform this protein, EhCaBP2. Both EhCaBPs have four canonical EF-hand...