| Summary: | We investigated biostimulation as an effective strategy for enhancing the degradation efficiency of recalcitrant organic compounds, with MSC14 (a novel polycyclic aromatic hydrocarbon degrading bacterium <i>Pantoea dispersa</i> MSC14) as the study material. Here, we investigated the impact of sodium gluconate on MSC14-mediated degradation of B[a]p. This study focused on the application of sodium gluconate, a biostimulant, on MSC14, targeting Benzo[a]pyrene (B[a]p) as the model pollutant. In this study, the novel PAHs-degrading bacterium <i>P. dispersa</i> MSC14 demonstrated the capability to degrade 24.41% of B[a]p after 4 days. The addition of the selected sodium gluconate stimulant at a concentration of 4 g/L stimulated MSC14 to degrade 54.85% of B[a]p after 16 h. Intermediate metabolites were analyzed using gas chromatography-mass spectrometry to infer the degradation pathway. The findings indicated that sodium gluconate promoted the intracellular transport of B[a]p by MSC14, along with the secretion of biosurfactants, enhancing emulsification and solubilization capabilities for improved B[a]p dissolution and degradation. Further analysis through transmission electron microscopy (TEM) and scanning electron microscopy (SEM) revealed the formation of a biofilm by MSC14 and an increase in flagella as a response to B[a]p stress. Transcriptome profiling elucidated the interplay of quorum sensing systems, chemotaxis systems, and flagellar systems in the degradation mechanism. Additionally, the study uncovered the molecular basis of B[a]p transport, degradation pathways, metabolic changes, and genetic regulation. In summary, the addition of sodium gluconate promotes the degradation of B[a]p by <i>P. dispersa</i> MSC14, offering the advantages of being rapid, efficient, and cost-effective. This research provides an economically viable approach for the remediation of petroleum hydrocarbon pollution, with broad potential applications.
|
|---|