Multiomics Analysis Revealed Anti-freezing Mechanism of Staphylococcus aureus in Its Anti-freezing Strain
Frozen food is currently a common food type. However, the presence of Staphylococcus aureus contamination caused serious challenge to frozen food safety. In this study, we explored the differences between sensitive strains and anti-freeze strains through multiomics analysis such as proteomics, phosphorylated proteomics, and metabolomics studies to understand the anti-freezing mechanism of S. aureus. This study compared the proteomics, phosphorylated proteomics and metabolomic differences between anti-freeze strains and sensitive strains before and after freezing. Before and after freezing, the differential protein-enriched channels changed from fructose-6-phosphate pathway, arachidonic acid metabolism pathway, atrazine degradation pathway to atrazine degradation pathway, starch and sucrose metabolism pathway, cysteine and methionine metabolism pathway, nitrogen metabolism pathway. In addition, this study inferred that pgi gene, ureA (urease subunit {gamma}), ureB (urease subunit ), ureC (urease subunit {beta}) gene, mtlD gene, fruB gene and asd gene could be crucial genes for the anti-freezing mechanism of S. aureus, which needs further investigation. Furthermore, the experimental results showed that PfkA, DeoC and Fda proteins from S. aureus were the key proteins for anti-freezing. They correspondingly involved in carbon fixation, fructose and mannose metabolism, and glycolysis/gluconeogenesis pathways in photosynthetic organisms. Finally, important metabolic pathways involved in the anti-freezing mechanism, mainly ABC transport pathway, amino acid metabolism pathway and secondary metabolite anabolic pathway.