Fig. 5.

Metabolomics analysis of Rhizobium cells treated with 2 mM H₂O₂, as generated by MetaboAnalyst 5.0. A PCA scores plot indicating differences in metabolic profiles in H₂O₂-treated and control (untreated) samples (n = 3); B heat map depicting the top 10 most significantly affected metabolites after H₂O₂ treatment, annotated using the Unified CCS Compendium. The experimentally measured CCS values and ΔCCS values (measured CCS–Unified CCS Compendium) are presented; red indicates an increase and blue indicates a decrease, based on OD₆₀₀-normalized and log-transformed intensities; C scatter plot of KEGG metabolic pathways in Rhizobium cells affected by H₂O₂ treatment, showing log p values from the pathway enrichment analysis (darker color indicates more significant changes within a pathway) and pathway impact values from the pathway topology analysis (the size of the node corresponds to the pathway impact score); significantly impacted pathways are annotated. KEGG purine metabolic pathway is focused upon as an example, depicting six putatively identified purine metabolites, out of which hypoxanthine and xanthine increased significantly after H₂O₂ treatment (color gradient from yellow to red indicates increasing significance values). The boxplots corresponding to the six metabolites represent the median ± IQR of OD₆₀₀-normalized, log-transformed and auto-scaled intensities. 1,2-DHPE 1,2-Diheptadecanoyl-sn-glycero-3-phosphoethanolamine, ATP adenosine triphosphate, C control, GDP guanosine diphosphate, Ile L-Isoleucine, IMP inosine monophosphate, Leu L-Leucine, Val L-Valine