Antifungal Activities of Peptides Derived from Domain 5 of High-Molecular-Weight Kininogen
Figure 2
Antifungal activity of rD5 and the D5-derived peptide HKH20. (a) In viable count assay, antifungal activities of rD5 and HKH20 were detected. 1 ×106 cfu mL−1 of C. parapsilosis ATCC 90018 was incubated in 50 μL with rD5 or HKH20 at concentrations ranging from 0.3 μM to 60 μM. (b) C. parapsilosis ATCC 90018 was subjected to rD5, HKH20, and the reference peptides LL-37 and Histatin-5 in RDA, each well was loaded with 6 μl of peptide at the indicated concentrations. (c) The indicated D5-derived peptides (6 μL each at 100 μM) were tested in RDA in low salt conditions against C. albicans ATCC 90028. GGH20, HKH20, and GKH17 showed antifungal activity. For comparison, the reference peptide LL-37 is shown. * indicates a statistically significant difference () in comparison to LL-37. (d) Time-dependent killing of C. parapsilosis ATCC 90018 by 30 μM HKH20 was analyzed by viable count assay. (e) M. furfur ATCC 44342 in a suspension of 1-2 × 105 cells/mL was added to buffer only (control, striped) or subjected to 10 μM (light gray) or 30 μM (dark gray) of the AMPs LL-37, HKH20, or GKH17 and incubated for 24 h. (f) M. furfur ATCC 44342 was subjected to increasing concentrations of GKH17 (filled circle) and HKH20 (open circle) and incubated for 24 h, and the percentage of survived yeast cells is shown. (g) Fluorescence microscopy shows binding of Texas Red-labeled HKH20 peptide (10 μM mL−1) to Candida cells. Panel 4 shows yeast cells incubated with heparin and Texas Red-labeled HKH20. Images in panel 2 and 4 were recorded using identical instrument settings. The corresponding Nomarski images are shown in panels 1 and 3. Data represents the mean of at least duplicate determinations from a single experiment representative of at least two experiments.
