A Peptide-Coated Gold Nanocluster Exhibits Unique Behavior in Protein Activity Inhibition.

Gold nanoclusters (AuNCs) can be primed for biomedical applications through functionalization with peptide coatings. Often anchored by thiol groups, such peptide coronae not only serve as passivators but can also endow AuNCs with additional bioactive properties. In this work, we use molecular dynamics simulations to study the structure of a tridecapeptide-coated Au25 cluster and its subsequent interactions with the enzyme thioredoxin reductase 1, TrxR1.

The Au clusters induce tumor cell apoptosis via specifically targeting thioredoxin reductase 1 (TrxR1) and suppressing its activity.

Au25 clusters stabilized by tridecapeptides were firstly synthesized, which can well penetrate the cell membrane and exactly locate in the cytoplasm. Hence the Au clusters significantly suppress the TrxR1 activity in the cytoplasm, and further induce the up-regulation of the activated PARP level which allows the tumor cell apoptosis to occur in a Au dose dependent manner.