3.6 Influence of indoxyl on intracellular redox status
To explore the influence of indoxyl on the intracellular redox status ofS. aureus , the activity level of cells was studied and analyzed
during cell growth. As shown in Fig. 6a, indoxyl increased the level of
intracellular peroxide, indicating that it affected the intracellular
redox status. Moreover, the production of peroxides also has a very
large side effect on cell activity (Cui et al., 2019). The results were
also consistent with this conclusion (Fig. 3). As the main products in
the tricarboxylic acid (TCA) cycle, ATP and NADH can be used to
determine the growth of cells. The gradual decrease of intracellular ATP
content and increase of NAD+/NADH ratio confirmed the
inhibitory effect of indoxyl on the TCA cycle (Fig. 6a, c). Therefore,
it could be considered that indoxyl destroyed the TCA cycle and reduced
the generation of ATP and reducing power. The change in redox status
promoted the generation of H2O2, which
may damage cells through the oxidation of lipids, proteins and DNA.