Deletion of sRNA0024 Reduces Virulence of Pseudomonas plecoglossicida and Alleviates Host Immune Injury in Epinephelus coioides
Year: 2025
Type: article
Abstract: Visceral white spot disease caused by Pseudomonas plecoglossicida severely threatens marine aquaculture, highlighting the need for effective control strategies. To clarify the role of a novel small RNA, sRNA0024, in bacterial pathogenicity, we constructed an sRNA0024 deletion mutant (ΔsRNA0024) and compared its phenotype and virulence with those of the wild-type strain NZBD9. In vitro assays showed that deletion of sRNA0024 did not affect bacterial growth but significantly reduced biofilm formation and adhesion. In vivo infection experiments in orange-spotted grouper (Epinephelus coioides) demonstrated that the ΔsRNA0024 mutant had a 3.8-fold higher 50% lethal dose (LD50), improved host survival, and milder splenic lesions than the wild type. Histopathology and host transcriptome analyses revealed weakened activation of complement–coagulation cascades, neutrophil extracellular traps, leukocyte migration, and inflammatory signaling pathways, indicating a lower-intensity immune response. Bacterial transcriptomics showed that deletion of sRNA0024 was associated with reduced luxR expression and attenuated quorum-sensing–associated virulence traits, supporting a possible role for this small RNA in modulating luxR expression and QS-related host immunopathology. These findings identify sRNA0024 as an important contributor to the virulence of P. plecoglossicida and highlight the sRNA0024–luxR module as a potential antivirulence target for controlling visceral white spot disease in aquaculture.
Source: Animals
DOI: 10.3390/ani15243623
Authors: Lingmin Zhao, Yihai Ouyang, Jiang Zheng, Yujia Sun, Yingxue Qin, Meiqin Mao
Institution: Jimei University
Language: English
Subfield: Immunology
Field: Immunology and Microbiology
Domain: Life Sciences
Open Access status: gold
Estimated APC paid: $2,896
Awards: G2102159608, G2941922935
OpenAlex ID: W4417423045