Effect of cargo location on translocation of cell-penetrating peptide fusion proteins into Candida albicans cells

Resistance to antifungal drugs is an increasing issue in treating disease caused by the fungal pathogen Candida albicans. As a step towards new antifungal approaches, we investigated antifungal delivery of molecules to C. albicans cells using the cell-penetrating peptide, MPG, genetically fused to the model cargo, green fluorescent protein (GFP). We varied the orientation of the fusion of GFP to MPG and evaluated translocation into the cells. We found fusing the GFP to the C-terminus of the peptide resulted in translocation into almost 5% of C. albicans cells, while fusion of GFP to the N-terminus of the peptide resulted in translocation into less than 0.3% of cells. Our results indicate that fusion of cargo to the C-terminus of MPG is preferred for intracellular delivery of cargo, but further research to improve the efficiency of translocation into the cells is required