Regulatory Effect of Two Component Signal Transduction System saeRS on the Survival of Staphylococcus Epidermidis

Objective To investigate the survival ability of Staphylococcus epidermidis (S.epidermidis) wildtype (WT), saeRSmutant (SAE) and saeRS complementary (SAEC) strains under different concentrations of glucose. Methods We measured the survival ability, biofilm forming ability, medium acidity and antimicrobial susceptibility of S.epidermidisin medium containing different concentrations of glucose. Results Compared with WT, the survival ability, biofilm forming ability and resistance to antibiotics (such as penicillin, oxacillin, gentamicin, ciprofloxacin and amikacin) of saeRSmutant increased significantly in response to glucose. SAE and SAEC showed the strongest survival ability and biofilm forming ability when grown in medium containing 14 mmol/L glucose and 28 mmol/L, respectively. WT showed no significant different survival and biofilm forming abilities when cultured with various concentrations of glucose. The medium acidity of saeRSmutant (pH=8.07) was lower than the WT (pH=7.0) in the presence of 14 mmol/L glucose. Conclusion saeRS may influence the survival ability of S.epidermidis by affecting glucose utilization.