Inhibition of growth and gene expression in Staphylococcus aureus by anti-gyrA peptide nucleic acid.

Aim: Multidrug-resistant Staphylococcus aureus isolates have become a serious concern in clinical microbiology. Antisense strategy, which specifically targets essential genes, could be helpful. Materials & methods:S. aureus cultures were treated with peptide conjugate-peptide nucleic acid (PPNA) specific for the gyrA gene. In addition, antimicrobial synergy with ciprofloxacin was tested.

Results

The results indicated anti-gyrA-PPNA dramatically inhibited the growth of S. aureus isolates in Mueller Hinton Broth with complete elimination of bacteria observed on cell cultures. Specifically, PPNA reduced the gyrA transcripts up to 50%. With antisense interference, growth inhibition was augmented through combination with ciprofloxacin.

Conclusion

This study suggested that anti-gyrA-PPNAs could be introduced as a novel candidate for developing antisense antibiotic to treat all S. aureus infections.