Transcriptomic and Metabolomic Analysis Reveals Molecular Mechanism of Oxygen-Rich Vacancy Bi₂MoO₆ Photocatalytic...

Antibiotic-resistant bacteria are widely distributed and threaten public health. Photocatalytic antimicrobial technology can effectively inactivate multidrug-resistant bacteria without readily inducing resistance. We previously showed that oxygen-rich vacancy Bi₂MoO₆ (OBM) exhibits excellent activity against methicillin-resistant Staphylococcus aureus (MRSA), but the underlying molecular mechanisms remain poorly understood. Here, we employed integrated transcriptomics and metabolomics, with qRT-PCR validation, to systematically elucidate the antibacterial mechanism of OBM against MRSA. OBM treatment induced profound transcriptional and metabolic alterations: 231 differentially expressed genes and 206 differentially abundant metabolites were identified. Functional enrichment analysis revealed cooperative involvement in multiple critical pathways, including inhibition of amino acid biosynthesis and protein translation, disruption of cell wall and membrane integrity, induction of oxidative stress, collapse of energy metabolism (suppression of oxidative phosphorylation and impaired ATP synthesis), and imbalance in nucleotide metabolism (down-regulation of DNA helicase and mismatch repair genes, dysregulation of purine/pyrimidine metabolism). These findings demonstrate that OBM photocatalytically inactivates MRSA through a multi-target systemic attack at both the transcriptional and metabolic levels, providing a novel theoretical foundation for the development of photocatalytic materials aimed at controlling MRSA and other drug-resistant bacteria.