The aim of this study was to find the peptide ligands to inhibit Candida albicans secreted aspartyl
proteinase 2 (Sap2). First, a ligand library, containing 300 different peptides, was constructed, and their
interaction with Sap2 was separately calculated by molecular dynamic software. Second, 10 peptide
ligands with the lowest intermolecular energy were selected. Then, triangular gold nanoparticles were
synthesized, and separately conjugated with the peptide ligands. After synthesis, antifungal property
and Sap inactivation of conjugated triangular gold nanoparticles, peptide ligands, and naked triangular
gold nanoparticle were separately assessed, against thirty clinical isolates of C. albicans. In this study, we
measured the uptake of conjugated and naked nanoparticles by atomic adsorption spectroscopy. This
study showed that naked triangular gold nanoparticle and all conjugated triangular gold nanoparticles
had high antifungal activity, but no peptide ligands had such activity. Of 300 peptide ligands, the peptide
containing N-Cys-Lys-Lys-Arg-Met-Met-Lys-Ser-Met-Cys-C and its conjugate had the highest capability
to inhibit Sap. Moreover, the uptake assay demonstrated that triangular gold nanoparticles conjugated
with the peptide ligand had the highest uptake.
