Abstract: Objective To study the effect of DNase I on biofilm formation of Staphylococcus aureus. Methods The growth curve of
S. aureus was detected using a spectrophotometer. The adhesion of S. aureus was analyzed using flat colony counting method,
and the biofilm formation was assayed using the 96-well crystal violet staining method. Results Exposure to different
concentrations of DNase I did not obviously affect the growth of S. aureus but significantly inhibit the formation of bacterial
biofilms in a dose-dependent manner. DNase I inhibited the adhesion of S. aureus at different growth stages. When combined
with antibiotics, DNase I resulted in a significant decrease in the established biofilm biomass compared to antibiotics or DNase
I used alone. Conclusion DNase I can effectively inhibit biofilm formation of S. aureus and enhance the inhibitory effect of
antibiotics against S. aureus biofilms.