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Teixeira, J. P.

Publications and source records attributed to Teixeira, J. P..

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↗

Integrative Genomic and Structure-Based Prioritization of Molecular Targets in Multidrug-Resistant Salmonella enterica from Brazilian Poultry

Salmonella spp. remains one of the leading foodborne pathogens worldwide, and the circulation of multidrug-resistant strains in the poultry industry poses a significant challenge. In this study, five isolates from poultry litter swabs (commercial broiler chickens) belonging to the Salmonella Heidelberg and Salmonella Minnesota serovars were characterized using an integrated approach involving phenotypic resistance profiling, whole-genome sequencing, structural prioritization of molecular targets, and in silico screening of ligands. All isolates exhibited multidrug resistance phenotypes and genetic repertoires consistent with resistance to {beta}-lactams, sulfonamides, and tetracyclines, as well as determinants linked to efflux systems, virulence, and persistence. Genomic analysis allowed for the prioritization of five proteins for structural investigation: CTX-M-2, CMY-2, Sul2, AcrB, and SpvC. Sequence-structure validation revealed high correspondence between the proteins of the isolates and the experimental structures selected for CMY-2, Sul2, AcrB, and SpvC, while CTX-M-2 was modeled with high structural confidence. Molecular docking analyses with GNINA revealed distinct behaviors among the targets. Sul2 showed biological relevance but a more conservative structural response, with no significant gain after analog generation. In contrast, AcrB stood out as the most promising target, with analogs generated by BRICS yielding better scores and, in some cases, coherent international networks identified by PLIP. The results demonstrate that the integration of phenotype, comparative genomics, and structural prioritization constitutes a rational strategy for selecting targets and molecular candidates in multidrug-resistant avian strains of S. Heidelberg and S. Minnesota.

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↗