Peptoid Efficacy against Polymicrobial Biofilms Determined by Using Propidium Monoazide-Modified Quantitative PCR

Biofilms containing Candida albicans are responsible for a wide variety of clinical infections. The protective effects of the biofilmmatrix, the low metabolic activity of microorganisms within a biofilm and their high mutation rate, significantly enhance the resistance of biofilms to conventional antimicrobial treatments. Peptoids are peptide-mimics that share many features of host defence antimicrobial peptides but have increased resistance to proteases and therefore have better stabilityin vivo. The activity of a library of peptoids was tested against monospecies and polymicrobial bacterial/fungal biofilms. Selected peptoids showed significant bactericidal andfungicidal activity against the polymicrobial biofilms. This coupled with low cytotoxicity suggests that peptoids could offera new option for the treatment of clinically relevant polymicrobial infections