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Kapoor, J.

Publications and source records attributed to Kapoor, J..

8 recordsLinked to original sources

A Multi-Epitope Vaccine Design for Human Pasteurellosis using Outer Membrane β-barrel Proteins of Pasteurella multocida

Pasteurella multocida is a facultative anaerobic, Gram-negative coccobacillus that causes pasteurellosis in companion animals, livestock, and poultry and poses a significant zoonotic risk to humans through bite wounds, scratches, licking, and transfer of bodily fluids. Although vaccines are available for livestock and poultry, no vaccine is currently licensed for human use. In this study, we systematically identified and characterized 29 outer membrane {beta}-barrel (OMBB) proteins in P. multocida Past9 proteome and classified them into functional categories, including TonB-dependent receptors, porins, autotransporters, adhesins, and efflux pumps. B-cell, cytotoxic T-lymphocyte (CTL), and helper T-lymphocyte (HTL) epitopes were predicted from the identified proteins and screened based on antigenicity, non-allergenicity, and non-toxicity. Epitopes conserved across eight human-infecting P. multocida strains and located within the extracellular loop (ECL) region were incorporated into a multi-epitope vaccine (MEV) construct. The designed MEV was predicted to be antigenic, non-allergenic, and soluble. Its tertiary structural model was iteratively refined and validated. Molecular docking with human toll-like receptors 4/2 (TLR4/TLR2) predicted stable interactions, further supported by 100 ns molecular dynamics simulations. Immune simulation of the MEV construct predicted a strong simulated immune response. Furthermore, codon optimization and in silico cloning supported the feasibility of recombinant MEV expression in E. coli. The construct was benchmarked against OmpH, a well-known antigenic protein and exhibited broadly comparable predicted immune responses and receptor-binding energetics. This study proposes a designed MEV candidate against human pasteurellosis and highlights OMBB proteins as potential immunogenic targets for vaccine development.

bioinformatics↗

Design of a Multi-epitope Vaccine Against Human Glanders Targeting Outer Membrane β-barrel Proteins of Burkholderia mallei

Burkholderia mallei, a facultative intracellular Gram-negative pathogen, is the causative agent of glanders that primarily affects solipeds and is sporadically transmitted to humans. Current interventions mainly rely on antibiotics; however, increasing antimicrobial resistance and the lack of a licensed vaccine further complicate disease management. Surface exposed outer membrane {beta}-barrel (OMBB) proteins serve as excellent targets for vaccine development. In the present study, a consensus-based computational framework was employed on the B. mallei turkey2 proteome that identified 59 OMBB proteins - including porins, TonB receptors, autotransporters, and efflux components. These OMBB proteins were leveraged to predict B- and T-cell epitopes which were manually curated, and mapped onto the corresponding protein models to identify surface-exposed epitopes with direct accessibility to the host immune cells. These epitopes were linked together to construct a multi-epitope vaccine (MEV) that was predicted to be antigenic, and soluble upon overexpression. The tertiary structure of the MEV was generated which was used for molecular docking with TLR4 and TLR2. Molecular dynamics simulation and flexibility analysis confirmed the structural stability of the MEV-TLR4/TLR2 complexes. In-silico immune simulation showed the capability of MEV to induce a strong immune response. Codon optimization and in-silico cloning were performed to evaluate its efficient expression in the E. coli host. The findings suggest that surface exposed OMBB proteins can serve as promising antigenic candidates for designing an MEV construct.

bioinformatics↗

Deciphering the Molecular Structure of the Type III Secretion System in Chlamydia trachomatis for Structure-Based Therapeutic Targeting

Chlamydia trachomatis is an obligate intracellular pathogen that causes sexually transmitted infections and trachoma. Its persistent forms show reduced antibiotic susceptibility, creating a need for new antivirulence strategies. The C. trachomatis injectisome or type III Secretion System (T3SS) injects effector proteins into host cells, yet the molecular structure of the complete apparatus is unknown. Here, we identify and validate all 13 T3SS constituent proteins using TXSSScan and reverse-BLAST analysis, and model and assemble them into the complete T3SS apparatus using an integrated computational pipeline. Template-based modeling revealed a conserved architecture despite low sequence identity (18-46%), and the assemblies were validated stereochemically and energetically against homolog controls. Targeting the oligomerization interface of the CdsN ATPase through structure-based virtual screening of the e-Drug3D and IMPPAT libraries, followed by ADMET filtering, including predicted membrane permeability for intracellular targeting, identified three repurposable FDA-approved candidates: M Roflumilast, Elacestrant, and Tecovirimat. MM-GBSA calculations and molecular dynamics simulations confirmed stable complexes with two adjacent CdsN monomers. Elacestrant showed the most favorable binding free energy. These results provide the first molecular-level map of the C. trachomatis T3SS and a rational basis for antivirulence drug repurposing. Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=93 SRC="FIGDIR/small/723290v2_ufig1.gif" ALT="Figure 1"> View larger version (31K): org.highwire.dtl.DTLVardef@6893c8org.highwire.dtl.DTLVardef@1be5eddorg.highwire.dtl.DTLVardef@1462b25org.highwire.dtl.DTLVardef@1baadab_HPS_FORMAT_FIGEXP M_FIG C_FIG

bioinformatics↗

Structural Characterization of the Type IV Secretion System in Brucella melitensis for Virtual Screening-Based Therapeutic Targeting

Brucellosis is a globally important zoonotic disease caused by Brucella melitensis, the most virulent and clinically significant species affecting both humans and livestock. Unlike many Gram-negative pathogens, B. melitensis, a facultative intracellular pathogen, lacks conventional virulence factors and instead relies on specialized systems such as the Type IV Secretion System (T4SS) for secretion of effector proteins. In this study, an integrated computational pipeline was implemented to identify, model, and assemble the T4SS components, encoded by virB operon, from the complete B. melitensis proteome. Template-based modeling strategies were employed to generate structures of T4SS subcomplexes, referencing crystallographic data from E. coli T4SS. Structural superposition with E. coli homologs revealed highly conserved architecture despite only 30-50% sequence identity. Stereochemical validation confirmed high model quality and favorable interactions among most VirB protein pairs. Membrane insertion analysis of the membrane-embedded assemblies further corroborated the spatial orientation of the modeled T4SS. Potential of T4SS as a drug target was explored by targeting dimeric interface of VirB11 ATPase to disrupt protein-protein interactions that could disarm the pathogen. Virtual screening of compounds from DrugBank database revealed compounds with docking score [≤] -7.0 kcal/mol that were screened based on ADMET properties, yielding three promising candidates - Ezetimibe (Drug Id: DB00973), Chlordiazepoxide (Drug Id: DB00475), and Alloin (Drug Id: DB15477). MM-GBSA analysis estimated favorable binding free energies for these compounds and molecular dynamics simulation for 200 ns further confirmed the protein-ligand interaction stability. Collectively, these findings provide new insights into the architecture of B. melitensis T4SS and identify three potential drug molecules targeting T4SS. This supports FDA - approved drug repurposing as an effective strategy for anti-virulence therapy against Brucellosis. Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=103 SRC="FIGDIR/small/706537v1_ufig1.gif" ALT="Figure 1"> View larger version (46K): org.highwire.dtl.DTLVardef@847c4borg.highwire.dtl.DTLVardef@1fc2551org.highwire.dtl.DTLVardef@f62a7corg.highwire.dtl.DTLVardef@15f3468_HPS_FORMAT_FIGEXP M_FIG C_FIG

bioinformatics↗

Personalized real-time inference of momentary excitability from human EEG

The efficacy of transcranial magnetic stimulation (TMS) is often limited by non-adaptive protocols that disregard instantaneous brain states, potentially constraining therapeutic outcomes. Current EEG-guided approaches are hindered by their reliance on motor-evoked potentials (MEPs), which confound cortical and spinal excitability and restrict applications to the motor cortex, and a dependence on static biomarkers that cannot adapt to changing neurophysiological patterns. We introduce PRIME (Personalized Real-time Inference of Momentary Excitability), a deep learning framework that predicts cortical excitability, quantified by TMS-evoked potential (TEP) amplitude, from raw EEG signals. By targeting cortical excitability directly, PRIME enables brain state-dependent stimulation across any cortical region. PRIME incorporates transfer learning and continual adaptation to automatically identify personalized biomarkers, allowing stimulation timing to be adapted across individuals and sessions. PRIME successfully predicts cortical excitability with minimal latency, providing a computational foundation for next-generation, personalized closed-loop TMS interventions.

neuroscience↗

Identification and Characterization of Outer Membrane Proteins and Membrane Spanning Protein Complexes in Brucella melitensis

Brucellosis (Malta fever) is a zoonotic disease that affects both humans and animals, including cattle, sheep, and goats. Brucella melitensis is the most virulent and clinically significant species in humans. It is a Gram-negative bacterium with three groups of outer membrane proteins (OMPs): minor OMPs (Group 1), and major OMPs (Groups 2 and 3). OMPs with {beta}-barrel architecture play important roles in nutrient transport, efflux, adhesion, and membrane biogenesis. Despite their importance, the structure, function, and interaction dynamics of several B. melitensis {beta}-barrel OMPs and associated protein complexes remain mostly unexplored. In this study, we conducted a comprehensive in silico analysis to characterize known outer membrane {beta}-barrel (OMBB) proteins and identify novel OMBBs in B. melitensis 16M. Proteins were modelled using five computational tools: AlphaFold 3, ESMFold, SWISS-MODEL, RoseTTAFold, and TrRosetta. Outer-membrane insertion of the novel OMBBs was confirmed using PPM 3.0, Protein GRAVY, DREAMM, and MemProtMD_Insane. Putative functions were predicted using structure- and sequence-based annotations. Sequence variation across 46 B. melitensis strains were identified and mapped onto the structural models. OMBB-associated protein complexes - the RND (Resistance-Nodulation-Division) efflux pumps, the lipopolysaccharide transport (Lpt) complex, and the {beta}-barrel assembly machinery (BAM) complex - were modelled, and protein-protein interactions (PPIs) were analyzed to confirm thermodynamically stable assemblies. This study presents a robust in silico strategy for exploring OMP architecture and provides valuable structural insights to support the development of diagnostics, targeted therapeutics, and vaccines against B. melitensis.

bioinformatics↗

Design of a Multi-Epitope Vaccine using β-barrel Outer Membrane Proteins Identified in Chlamydia trachomatis

Chlamydia trachomatis is an obligate intracellular Gram-negative pathogen responsible for causing sexually transmitted infections (STIs) and trachoma. Current interventions, including screening and antibiotics, are limited due to the widespread nature of asymptomatic infections, and the absence of licensed vaccine exacerbates the challenge. In this study, we predicted outer membrane {beta}-barrel (OMBB) proteins and designed a multi-epitope vaccine (MEV) construct using identified proteins. We employed a consensus-based computational framework on the C. trachomatis D/UW-3/CX proteome and identified 17 OMBB proteins, including well-known Pmp family members and MOMP. Eight OMBB proteins were computationally characterized, which showed significant structural homology with known outer membrane proteins from other bacteria. Sequence-based annotation tools were used to determine their putative functions. B-cell and T-cell epitopes were predicted from the selected proteins. The MEV construct was designed using four cytotoxic T lymphocyte (CTL) epitopes and 29 helper T lymphocyte (HTL) epitopes predicted from six OMBB proteins, which were conserved across 106 C. trachomatis serovars. The vaccine was supplemented at the N-terminus with Cholera enterotoxin subunit B and PADRE sequence to enhance its immunogenicity. The MEV construct of 780 amino acids was antigenic, non-allergenic, non-toxic, and soluble. Secondary structure analysis revealed 95% random coils. The 3D structural model of MEV was generated and validated, confirming its structural reliability. Molecular docking between MEV and Toll-like receptor 4 (TLR4) revealed strong and stable binding interactions, supporting its potential to elicit a strong immune response. This study highlights OMBB proteins as promising immunogenic targets and presents a computationally designed MEV candidate for C. trachomatis infection.

bioinformatics↗

Identification and Characterization of Novel Outer Membrane Proteins of Brachyspira pilosicoli

Brachyspira pilosicoli is a pathogenic, Gram-negative, spirochete bacterium that causes intestinal spirochetosis (IS) in birds, pigs, and humans and is distributed worldwide. This anaerobic intestinal bacterium colonizes the large intestine, potentially leading to colitis, diarrhoea, and decreased growth rate. Outer membrane proteins of Gram-negative bacteria play crucial roles in adhesion and host-pathogen interaction, helping the bacteria to evade the host immune system, and enhancing their virulence. However, B. pilosicoli outer membrane proteins are yet to be identified and characterized. Here, we report the computational discovery of 42 outer membrane {beta}-barrel (OMBB) proteins in B. pilosicoli proteome predicted using a consensus-based computational framework. {beta}-barrel architectures of the predicted proteins were confirmed by generating AlphaFold 3-based structural models. Structure-based functional annotation predicted putative functions for the identified OMBB proteins, including BamA homolog involved in folding and membrane insertion of OMPs, LptD homolog involved in transport of lipopolysaccharides into the OM, efflux pumps, transporters, enzymes, diffusion channels, and porins. Sequence variations across nine strains of B. pilosicoli were identified and mapped onto structural models, revealing that many of the variations were present on the surface exposed loop regions of the {beta}-barrel structures. Our in-silico analysis has identified 42 OMBB proteins, including homologs of BamA, LptD, TolC, TonB-dependent receptors, CsgG. Seven of these were identified as hypothetical proteins. Computational characterization of the predicted OMBB proteins offer insights into their potential roles in physiology, virulence, and disease pathogenesis, highlighting their potential for applications in diagnostics, vaccine development, or therapeutic interventions.

bioinformatics↗