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Freire, C. C. d. M.

Publications and source records attributed to Freire, C. C. d. M..

4 recordsLinked to original sources

Genotype-Resolved Interaction Landscape of the Dengue Envelope Glycoprotein with Host Cellular Proteins: Structural Dynamics, Thermodynamic Cooperativity, and Binding Specificity

1Dengue virus (DENV) entry has historically been viewed as a receptor-centric process in which viral envelope proteins engage isolated host factors to initiate infection. However, mounting evidence reveals that viral attachment, internalization, and intracellular trafficking occur within complex molecular environments where multiple interacting host proteins shape the infection landscape. Here we introduce vectorial host interaction fields--a framework that represents intermolecular contacts as directional vectors embedded within host protein interaction networks, providing structural and systems-level insight into viral entry. Docking analyses were performed across sixteen dengue envelope genotype variants, whereas molecular dynamics and MM/GBSA analyses were conducted on representative complexes selected from this genotype-informed screening. We characterized dengue envelope interactions with thirteen host proteins involved in membrane attachment, receptor signaling, cytoskeletal transport, vesicular trafficking, proteostasis, and immune regulation. Our multiscale approach integrated protein-protein docking, 200 ns molecular dynamics simulations of representative complexes, MM/GBSA binding free energy analysis, and vectorial hydrogen-bond formalism encoding orientation, persistence, and angular entropy. We identified four recurrent viral interface architectures: multivalent anchoring (BiP/GRP78, Betaglycan), electrostatic sliding (Glypican-1), focal regulation (Claudin-1, SUMO), and conserved cytoskeletal modules (Actin, Rab5). Ternary docking analyses revealed that viral stability is strongly conditioned by local network context, with conditional {Delta}{Delta}G values ranging from approximately -3.4 to +6.9 kcal mol-1 depending on neighboring proteins and assembly sequence. These findings support a systems-level model of dengue entry driven by layered host interaction fields rather than a single dominant receptor, but they should be interpreted as computational structural hypotheses requiring biochemical, biophysical, and cellular validation. Detailed structural datasets, molecular dynamics trajectories, vectorial analyses, and per-residue MM/GBSA decomposition are provided in the companion Supplementary Material, which includes extended Results and Discussion, comprehensive Limitations assessment, and VectorPROT pipeline documentation supporting these findings.

biophysics↗

Pressure-cooling remodeling of TMV coat protein reveals mechanically partitioned capsid dynamics and selective epitope masking

High hydrostatic pressure (HHP) perturbs protein assemblies by shifting conformational equilibria toward lower-volume states and by reorganizing hydration at cavities, interfaces, and solvent-exposed surfaces (Heremans 1982; Akasaka 2006; Roche et al. 2012; Hata, Nishiyama, and Kitao 2020). Here, we integrate pressure-dependent molecular dynamics descriptors, pressure-temperature interpretation, structure-based epitope prediction, and face-resolved intersubunit metrics to examine how pressure and pressure-cooling treatment remodel the tobacco mosaic virus coat protein (TMVcp) assembly. The pressure response is not adequately explained as uniform shrinkage. Instead, the data support a hierarchical transition from a broad, native-like conformational ensemble at low pressure, through a cooperative compacting regime around 1000- 1750 bar, toward a high-pressure compact state with reduced configurational diversity, suppressed global mobility, and localized residual fragility. A representative TMVcp face composed of A2, A3, A4, A19, A20, A21, A35, A36, and A37 behaves as a mechanically partitioned network: A3 behaves as a principal deformation hub, A20-A21-A35-A37 forms a lateral/diagonal compression corridor, A21 behaves as a bridge node, A36 acts as an anisotropic relay, and A2, A4, and A19 behave as stabilizing or adaptive anchors. Pairwise minimum-distance profiles, per-subunit radius of gyration, and post-fit RMSD converge around a late trajectory interval near 358-365 ns, suggesting a coordinated face-level breathing event rather than independent stochastic noise. These local dynamics provide a conservative structural explanation for predicted pressure-dependent epitope remodeling: HHP may mask canonical solvent-exposed epitopes by reducing loop mobility and closing intersubunit grooves, whereas pressure followed by low-temperature trapping may selectively preserve only protrusions compatible with the compact, hydration-trapped lattice. Because DiscoTope and ElliPro are computational predictors, these results should be interpreted as structural hypotheses requiring experimental validation by antibody binding assays, mutagenesis, HDX-MS, or high-pressure structural approaches.

microbiology↗

An Open-Source Reproducible Workflow for Pocket-Oriented Virtual Screening and ADME-Integrated Chemoinformatics: A Multi-Target Flavivirus Case Study

Zika virus (ZIKV), yellow fever virus (YFV), West Nile virus (WNV), Usutu virus (USUV), and Saint Louis encephalitis virus (SLEV) remain major public health concerns, yet broad-spectrum antiviral options are limited. Here, we present an open-source, reproducible software workflow for pocket-oriented virtual screening and ADME-integrated chemoinformatics, designed to support standardized multi-target compound prioritization. As a case study, the workflow was applied to structural and nonstructural proteins from clinically relevant flaviviruses. Automated pocket detection using Concavity reduces site-selection bias by generating docking boxes from surface concavity clusters, while standardized downstream scripts parse docking logs, convert docking-derived binding energies into Kd-related metrics, integrate SwissADME descriptors, and compute LE, LLE, FQ, and drug-likeness rules. The framework also supports retrospective validation and comparative benchmarking using literature-supported reference compounds and target-specific plausibility checks. Rather than proposing experimentally validated antiviral candidates, this study provides a reusable computational framework for hypothesis generation, benchmarking, and downstream experimental prioritization in structure-based drug discovery. The workflow is modular and adaptable to other multi-target screening campaigns where integrated ranking across binding, physicochemical, and ADME dimensions is required. SUMMARYWe describe an open-source, reproducible software workflow that integrates pocket-oriented docking, ligand efficiency scoring, ADME descriptor integration, and multivariate chemoinformatics to standardize compound prioritization across multiple protein targets. The workflow combines open-source tools with auditable Bash, R, and Python scripts and is demonstrated through a multi-target flavivirus case study. Rather than claiming experimentally validated antiviral activity, the framework is intended to support hypothesis generation, retrospective benchmarking, transparent reporting, and downstream experimental prioritization.

bioinformatics↗

Integrative Proteome-Wide Structural Analysis and High-Throughput Docking Identify Broad-Spectrum Antiviral Scaffolds Against Zika, Yellow Fever, West Nile, Saint Louis Encephalitis, and Usutu Viruses

Integrative proteome-wide virtual screening offers a powerful route to discover broad-spectrum antivirals against emerging flaviviruses, for which no approved therapeutics currently exist. Here, we address this gap by constructing homology models of all structural and nonstructural proteins from Zika, Yellow Fever, West Nile, Saint Louis Encephalitis, and Usutu viruses. We applied a standardized pipeline--combining sequence and structure based pocket prediction (Concavity), electrostatic profiling (APBS), and pharmacokinetic filtering (Lipinskis rules, ADMET)--to generate high-confidence binding sites. A focused library of 160 natural product scaffolds and repurposed antivirals was then docked exhaustively (2,000 runs per pocket) using AutoDock4/Vina, followed by clustering and ranking by binding energy. Comparative analyses (RMSD, PCA, RMSF) confirmed conserved core folds alongside virus-specific surface signatures, guiding grid definition. Of the 45 top-ranked scaffolds, several flavonoids exhibited dual-site binding to the NS5 polymerase and E glycoprotein across [≥]4 viruses, while ribavirin and sofosbuvir engaged conserved catalytic motifs in NS3/NS5, highlighting opportunities for combination strategies. Lead compounds such as myricetin (Kd {approx} 1.9 {micro}M), temoporfin (Kd {approx} 1.2 nM), and aurintricarboxylic acid (Kd {approx} 1.9 {micro}M) demonstrated favorable multitarget profiles. This integrative framework prioritizes robust candidates for experimental validation and optimization of panflaviviral therapeutics.

microbiology↗