{"database":"bioimages","file_versions":[],"scores":null,"additional":{"omics_type":["Unknown"],"submitter":["Nayma Romo Bechara"],"full_dataset_link":["https://www.ebi.ac.uk/biostudies/studies/S-BIAD2916"],"repository":["bioimages"],"figure_sub":["Specimen","Funding","Study Component","Biosample","organisation","Associations","Image acquisition"],"pubmed_authors":["Kasie Raymann","Nayma Romo Bechara"],"additional_accession":[]},"is_claimable":false,"name":"SEM images from Parallel and Divergent Evolution in Pseudomonas aeruginosa under Stable and Fluctuating Predator-Mediated Selection\n","description":"Environmental predation is a major driver of bacterial evolution and may indirectly shape virulence through coincidental selection. However, how sustained versus fluctuating predator pressure influences long-term adaptive trajectories remains poorly understood. Here, we used experimental evolution to investigate the genetic and phenotypic responses of Pseudomonas aeruginosa to continuous, absent, or fluctuating exposure to the protozoan predator Tetrahymena thermophila over 180 days. Whole-population and isolate-level shotgun metagenomic sequencing revealed increasing mutation frequencies over time, extensive site-specific parallel evolution, and signatures of positive and purifying selection, with evidence of balancing selection under fluctuating conditions. High-frequency mutations targeted diverse functional pathways, indicating both shared and condition-specific adaptive responses. Phenotypic assays revealed widespread changes in motility, biofilm formation, siderophore production, protease activity, hemolysis, and cell size, while overall virulence in an invertebrate host model remained unchanged. Correlation analyses uncovered coordinated phenotypic shifts and genotype–phenotype associations, highlighting trade-offs among virulence-associated traits. Together, our results demonstrate that temporal variation in predator-mediated selection shapes both the pace and targets of bacterial adaptation, constraining the retention of virulence-related traits and emphasizing the ecological context underlying opportunistic pathogenicity.\n","dates":{"release":"2026-03-11T00:00:00Z","modification":"2026-06-16T10:31:02.851Z","creation":"2026-02-10T22:40:30.957Z"},"accession":"S-BIAD2916","cross_references":{}}