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Negron, O.

Publications and source records attributed to Negron, O..

2 recordsLinked to original sources

Spatial transcriptomics identifies the Pseudomonas aeruginosa major outer membrane protein OprF as a critical factor in blinding corneal infections

Pseudomonas aeruginosa is a globally recognized pathogen causing pulmonary, skin, and severe corneal infections (keratitis), with the potential to induce irreversible blindness if untreated. Spatial transcriptomic analysis of P. aeruginosa infected corneas identified elevated expression of the outer membrane proteins OprF and OprL and PA1414, which encodes the small RNA SicX in the corneal stroma compared with corneal epithelium. Comparative spatial transcriptomics analysis of corneas infected with an oprF transposon (TN) mutant showed reduced expression of the type III effector protein ExoT, which was absent in an oprF deficient mutant ({Delta}oprF) and in contrast to PA14, did not inhibit reactive oxygen species (ROS) production by neutrophils. Corneal infection with the {Delta}oprF mutant resulted in reduced corneal virulence and lower CFU compared to the parental PA14 strain. Collectively, our findings demonstrate a coordinated virulence program connecting OprF functionality with the release of ExoT and its ability to block ROS production and survive in infected corneas.

microbiology↗

Spatial transcriptomics identifies novel P. aeruginosa virulence factors

To holistically unravel the complexity of pathogen-host interactions within infected tissues we leverage a dual spatial transcriptomic approach that, for the first time, simultaneously captures the expression of Pseudomonas aeruginosa genes alongside the entire host transcriptome in a model of ocular infection. This innovative method reveals differential pathogen and host-specific gene expression patterns across specific anatomical regions generating a unified transcriptional map of infection. By integrating these data, we developed a predictive ridge regression model trained on images from infected tissues. The model achieved an R{superscript 2} score of 0.923 in predicting bacterial burden distributions by using host features thereby predicting novel biomarkers associated with disease severity. Our analysis revealed a complex interplay between P. aeruginosa nutritional requirements and protective host responses and identified novel interactions between bacterial metabolite transport proteins and host autophagy. Among an array of iron acquisition gene transcripts that showed significant enrichment at the host-pathogen interface, we discovered a novel virulence mediator PA2590. This study highlights the power of spatial transcriptomics, particularly in combining bacterial and host transcriptomes, to uncover novel host-pathogen interactions, advance our understanding of bacterial virulence mechanisms, and point to druggable molecules.

microbiology↗