Browsing by Author "Moreno-Morales, Gerald"

Filter results by typing the first few letters
Now showing 1 - 2 of 2
  • Thumbnail Image
    Item
    Complete mitochondrial genome assembly and analysis of a Neotropical lineage of Ligula intestinalis reveals evolutionary and phylogenetic insights
    (Springer Science and Business Media LLC, 2026-02-17) Mondragón-Martínez, Aarón Maguín; Martínez-Rojas, Rosa; Gárate, Inés; Sánchez-Venegas, Jaime R; Moreno-Morales, Gerald; Cruz-Neyra, Lidia; Cruces, Celso Luis; García-Candela, Jose Luis Enrique; Guzman-Escudero, Frank; Chero, Jhon D; Yunis-Aguinaga, Jefferson; Štefka, Jan; Nazarizadeh, Masoud
    Ligula intestinalis (Cestoda: Diphyllobothriidea) is a cosmopolitan tapeworm parasite characterized by a complex life cycle that includes freshwater fish infection. Ligula disrupts host reproduction, and causes ecological imbalances. Despite its broad geographic distribution and ecological significance, molecular data for South American populations have been lacking, leaving a critical gap in understanding its genetic diversity and evolutionary history. To address this, we conducted the first molecular characterization of L. intestinalis plerocercoid larvae isolated from the native fish Orestias agassizii in Lake Titicaca, Peru. Using Illumina next-generation sequencing, we assembled a complete mitochondrial genome of 13,657 bp, containing 12 protein-coding genes, 22 tRNA genes, two rRNA genes, and two non-coding regions. The mitogenome exhibited an A + T-rich composition (66.3%) and contained over 580 repetitive elements, primarily concentrated within its control region. Comparative analyses with European and Asian mitogenomes revealed substantial regional differences in nucleotide diversity and amino acid composition, with closer similarity observed between South American and Asian lineages. Genes atp6, nad5, and nad6 showed the highest variability, whereas cox1 demonstrated significant intercontinental divergence yet remained conserved within South America, reflecting both phylogeographic patterns and strong functional constraints. Phylogenetic inference based on mitochondrial markers (cytb, cox1, and nd1) confirmed the Titicaca specimen as a distinct South American lineage, closely related to the Nearctic lineage. These findings enhance our understanding of L. intestinalis mitogenomic diversity, emphasize the importance of geographic isolation in parasite diversification, and provide an essential genomic resource for future evolutionary and ecological research in high-altitude ecosystems.
  • Thumbnail Image
    Item
    Phylogenomic and comparative genomic analyses of Aeromonas spp. from South American aquatic systems reveal extensive genomic diversity, antimicrobial resistance, and predicted human pathogenicity
    (Frontiers Media SA, 2026-06-16) García-Candela, Jose Luis Enrique; Mondragón-Martínez, Aarón Maguín; Moreno-Morales, Gerald; Cabrera-Soregui, Milagros; Puicón-Niño-De-Guzmán, Víctor Humberto; Ramos-Gorbeña, Juan Carlos; Santa-Cruz, Alcides Guerra; Cruz-Neyra, Lidia; Solis-Sarmiento, Julio
    Introduction – Aquaculture systems function as dynamic ecological interfaces facilitating the circulation of opportunistic pathogens and antimicrobial resistance (AMR) determinants across environmental, animal, and human compartments. Aeromonas spp. are ubiquitous freshwater bacteria and emerging human opportunistic pathogens, yet genomic data from tropical South American aquaculture remain scarce. Methods – Nine Aeromonas isolates from Amazonian aquaculture facilities in Peru were subjected to whole-genome sequencing. Species identification was performed using Average Nucleotide Identity and phylogenomic reconstruction within a dataset of 112 genomes. Ribosomal MLST, comparative gene content analysis, virulence and resistome profiling, human pathogenicity prediction, and quinolone resistance-determining region (QRDR) screening were conducted. Phenotypic antimicrobial susceptibility testing was performed against five antibiotics. Results – Phylogenomic analysis revealed substantial genetic diversity among the analyzed isolates, encompassing Aeromonas hydrophila, Aeromonas caviae, and Aeromonas veronii, with no clustering by host species or production site. Ribosomal MLST assigned 8 distinct rSTs across the 9 isolates. Comparative genomic analysis identified 19, 486 gene clusters, of which a subset was shared across all genomes, while the majority were variably distributed, indicating extensive genomic diversity across Aeromonas spp. All isolates shared conserved colonizationand secretion-associated determinants, whereas major cytotoxic toxin genes were absent. PathogenFinder v2 predicted high probabilities of human pathogenicity (0.93–0.96) across all genomes. Resistome analysis identified genes associated with tetracycline, quinolone, sulfonamide, and β-lactam resistance, including intrinsic blaOXA and cphA, while QRDR screening identified mutations potentially associated with quinolone resistance. Genomic findings were broadly consistent with phenotypic susceptibility profiles. Conclusion – Amazonian aquaculture systems harbor genetically diverse Aeromonas lineages with conserved opportunistic virulence traits and clinically relevant AMR determinants. These findings highlight the role of aquaculture environments as reservoirs and potential transmission interfaces of antimicrobial resistance and opportunistic pathogens, underscoring the importance of genomic surveillance within a One Health context.