Enzymatic Activity Profiling in S. aureus

Commercially available colorimetric assay kits of enolase (Abcam), pyruvate dehydrogenase (Abcam), phosphofructokinase (Abcam), and lactate dehydrogenase (Abcam) were used to measure corresponding enzymatic activities. In brief, S. aureus cell cultures with or without treatment of AgNO₃ were harvested, washed, suspended, and sonicated in lysis buffers. The protein concentration of supernatant after centrifugation was measured by BCA assay. Enzyme activities were measured according to the standard procedures provided by the manufacture. The enzymatic activity was normalized to protein concentration. The activity of alkyl hydroperoxide reductase⁷⁰ , Pgl^{71 (link)}, and 6PGDH^{72 (link)} were performed according to previous reports.