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The emergence of drug resistance to <i>Candida albicans</i> is problematic in the clinical setting. Therefore, developing new antifungal drugs is in high demand. Our previous work indicated that the antimicrobial peptide P-113Tri exhibited higher antifungal activity against planktonic cells, biofilm cells, and clinical isolates of <i>Candida</i> species compared to its parental peptide P-113. In this study, we further investigated the difference between these two peptides in their mechanisms against <i>C. albicans</i>. Microscopic examination showed that P-113 rapidly gained access to <i>C. albicans</i> cells. However, most of the P-113Tri remained on the cell surface. Moreover, using a range of cell wall-defective mutants and competition assays, the results indicated that phosphomannan and N-linked mannan in the cell wall are important for peptide binding to <i>C. albicans</i> cells. Furthermore, the addition of exogenous phosphosugars reduced the efficacy of the peptide, suggesting that negatively charged phosphosugars also contributed to the peptide binding to the cell wall polysaccharides. Finally, using a glycan array, P-113Tri, but not P-113, can bind to other glycans commonly present on other microbial and mammalian cells. Together, these results suggest that P-113 and P-113Tri have fundamental differences in their interaction with <i>C. albicans</i> and candidacidal activities.