Staphylococcus aureus

RNAIII-inhibiting peptide(TFA) is a potent inhibitor of Staphylococcus aureus . RNAIII-inhibiting peptide (RIP) inhibits the synthesis of both RNAII and RNAIII, while RAP activates in wild type S. aureus cells. RNAIII-inhibiting peptide (5 μg/10 ⁶ cells) potently reduces bacterial cell adhesion to HEp2 cells in the absence of serum, but with slight overall reduction the presence of serum. RNAIII-inhibiting peptide inhibits while RAP induces the phosphorylation of TRAP.

RNAIII-inhibiting peptide (20 mg/kg, i.v.) decreases lethality in mice challenged with S. aureus ATCC 25923, with the lethality rate of 70%, and when combined with cefazolin, imipenem, vancomycin, the rates are 20%, 15% and 10%. RNAIII-inhibiting peptide (20 mg/kg, i.v.) also causes decreased lethality in mice challenged with S. aureus Smith, with the lethality rate of 75%, and the lethality rate decreases to 30%, 10% and 10% when combined with cefazolin, imipenem, vancomycin.