Targeting of staphyloxanthin and α-hemolysin by natural compound L-Malic acid suppresses Staphylococcus aureus virulence

This dataset encompasses comprehensive experimental data generated to elucidate the regulatory effects of L-malic acid (L-MA) on the virulence, metabolism, and pathogenicity of Staphylococcus aureus HG003 and its derivatives (Δmqo, Δmqo-C), integrating in vitro, in vivo, and molecular biology assay results. All data were acquired following standardized protocols with biological triplicates and three technical replicates per experiment, ensuring reproducibility.For plasmid construction experiments, the dataset includes DNA sequencing data of recombinant plasmids (pkOR1-Δmqo, pYJ335-mqo-C, pLI50-crtO-C, pCL-crtO-lacZ, pET28a-crtM, pET28a-crtN) to confirm no PCR-induced mutations.Minimum inhibitory concentration (MIC) assay data record visible growth status of S. aureus in CAMHB with gradient L-MA concentrations, while growth curve data comprise hourly OD600 measurements (0-12 h) and 24 h time points, alongside 10-fold serial dilution-based CFU counts (0, 4, 8, 12 h) to assess viability. Data on mevalonic acid (MVA)-mediated growth modulation are included under the same experimental framework.Pigment production data consist of visual observation records and photos of bacterial colonies (on TSA plates) and pellets (after PBS washing) from L-MA-treated and control groups, documenting pigment intensity differences.Hemolytic activity data include photos of the supernatant obtained after incubating human red blood cells (RBC) and bacterial supernatants with centrifugation, as well as the hemolysis rate results of the corresponding positive/negative controls (Triton X-100, PBS).Western blot data include relative luminescence intensities of α-hemolysin (Hla) and the gray values quantified using the ImageJ software.Hydrogen peroxide and human whole blood killing assays provide CFU counts of viable bacteria post-incubation, reflecting bacterial antioxidant capacity and resistance to host-mediated killing.In vivo mouse infection model data include the diameter/area of skin abscesses (measured using digital imaging software) and bacterial load in the subcutaneous abscess model of BALB/c mice; the bacterial load in the liver and kidneys (the number of CFU per gram of tissue) in the bloodstream infection model. These data cover the measurement results of the treatment group (local application of L-MA or oral gavage) and the control group.Molecular assay data include RNA-seq datasets (Illumina HiSeq X platform, PE150) of S. aureus strains, with differentially expressed genes (DEGs) analyzed via DEGseq (log2 FC > 1, P < 0.005). RT-qPCR data consist of relative gene expression levels (calculated via the 2-ΔΔCt method) of target genes normalized to the endogenous control gyrB.β-galactosidase assay data consist of absorbance values at 416 nm (for o-NP detection) from ONPG-based reactions, normalized to bacterial OD600 values to calculate Miller units.Protein expression and purification data include SDS-PAGE gel images (Coomassie blue staining) of Ni-NTA column fractions (flow-through, imidazole eluates).Thermal shift assay data comprise densitometric gray values (ImageJ) of soluble CrtM/CrtN proteins post-thermal treatment (26.0-54.0℃), alongside SDS-PAGE gel images.All data are organized into Microsoft Excel (.xlsx), TIF (.tif) and JPG (.jpg) files, with individual files corresponding to specific assays (e.g., growth curves, CFU, RNA-seq). No missing data or experimental errors were observed; data were processed using GraphPad Prism 9 and ImageJ with statistical significance determined by unpaired two-tailed Student’s t-tests (P < 0.05). This dataset enables detailed validation and further exploration of L-MA’s role in regulating S. aureus virulence.