[WIP] Comparative Pangenomics of Marine Streptococcal Pathogens: Global Genomic Diversity and Evolutionary Dynamics in Aquaculture-Associated Bacteria

[WIP] - Global Pangenomics of Marine Streptococcal Pathogens: Evolutionary Dynamics, Species Boundaries, and Genomic Diversity in Aquaculture-Associated Bacteria Description This study presents the first comprehensive pangenomic analysis of major marine streptococcal pathogens threatening global aquaculture sustainability. Marine streptococcal infections cause over $250 million in annual losses worldwide, affecting 27+ fish species across all continents while developing alarming antibiotic resistance patterns that threaten both aquatic ecosystems and human health. Research Objectives This work aims to establish a comprehensive genomic framework for understanding marine streptococcal diversity, evolution, and pathogenicity through systematic analysis of RefSeq genomes representing seven major species: Streptococcus iniae, S. agalactiae, S. dysgalactiae, S. parauberis, S. uberis, S. phocae, and the related pathogen Lactococcus garvieae. Multi-Scale Comparative Genomics: The study employs species-specific pangenomes, population structure analysis, and comprehensive pairwise comparisons to understand evolutionary relationships, gene flow patterns, and adaptation mechanisms in marine environments. Advanced Visualization and Analysis: Implementation of UpSet plot visualization and modern pangenomic tools to identify gene sharing patterns between species and within population clusters, providing superior resolution for multi-species comparative analysis. Evolutionary and Ecological Insights: Characterization of adaptation mechanisms, horizontal gene transfer patterns, and population structure to understand how marine streptococci evolve and spread in aquaculture environments. Methodological Approach Standardized Pangenomic Pipeline: Utilizes Panaroo for robust pangenome construction with consistent parameters across species, enabling direct comparisons of genomic diversity patterns. Population Genetics Integration: Combines FastBAPS clustering with phylogenomic analysis to characterize population structure and evolutionary relationships within and between species. Advanced Visualization Framework: Implements UpSet plots for scalable visualization of gene sharing patterns across multiple species, providing superior resolution for complex multi-species comparisons. Comparative Genomics Framework: Integrates genomic conservation analysis, phylogenetic reconstruction, and functional annotation to identify core genetic elements and species-specific adaptations. Expected Impact Aquaculture Sustainability: Will provide the genomic framework needed for understanding pathogen diversity and developing improved diagnostic tools to reduce economic losses from streptococcal diseases. Public Health Protection: Aims to characterize zoonotic potential and transmission pathways of marine streptococci, addressing documented human infections and food safety concerns. Antimicrobial Stewardship: Seeks to identify conserved therapeutic targets that could guide development of alternatives to conventional antibiotics in the face of rising resistance. Pathogen Surveillance: Will establish genomic baselines for monitoring pathogen evolution and outbreak investigation in aquaculture systems worldwide. Technical Framework Comprehensive Dataset: Analysis of 800+ RefSeq genomes using standardized NCBI datasets Robust Software Pipeline: Integration of Panaroo, FastBAPS, IQ-TREE, and UpSetR for comprehensive analysis Scalable Infrastructure: Computational pipeline designed for high-performance computing environments Open Standards: Adherence to standard bioinformatics formats ensuring reproducibility and interoperability Significance This work addresses critical knowledge gaps in marine pathogen genomics that have hindered effective disease control in the rapidly expanding global aquaculture industry. The comprehensive pangenomic framework will provide the scientific foundation needed to understand pathogen evolution, diversity, and adaptation mechanisms that could inform sustainable aquaculture management and food security worldwide. Keywords pangenomics, aquaculture pathogens, Streptococcus, comparative genomics, evolutionary genomics, antibiotic resistance, marine microbiology, food security, One Health, phylogenomics Data and Code Availability All analytical workflows and custom scripts will be made available to ensure full reproducibility. The study follows FAIR data principles and provides detailed methodological documentation to facilitate adoption by the broader research community. Note This manuscript is currently in preparation. All methodological frameworks and analytical approaches described have been established, with data collection and analysis in progress.