Enzyme-Mimetic,
Cascade Catalysis-Based Triblock Polypeptide-Assembled
Micelles for Enhanced Chemodynamic Therapy
Posted on 2024-10-31 - 10:03
Peptides and their conjugates are appealing as molecular
scaffolds
for constructing supramolecular biomaterials from the bottom up. Through
strategic sequence design and interaction modulation, these peptides
can self-assemble into diverse nanostructures that can, in turn, mimic
the structural and catalytic functions of contemporary proteins. Here,
inspired by the histidine brace active site identified in the metalloenzyme,
we developed a triblock polypeptide with a hydrophobic polyleucine
segment, a hydrophilic polylysine segment, and a terminal oligohistidine
segment. This polypeptide demonstrates tunable and adaptive self-assembly
morphologies. Moreover, copper ions can interact with the oligohistidine
chelator and mediate the supramolecular assembly, generating metal–ligand
centers for redox flow. The triblock polypeptide-based peptide micelles
show Fenton-type activity with high substrate affinity when coassembled
with copper ions. We have also engineered therapeutic micelles by
coassembling two polypeptides, one integrated with copper ions and
the other conjugated with glucose oxidase. This coassembled nanoplatform
shows high in vitro and in vivo antitumor efficacy through a mechanism
that combines triggered starvation and chemodynamic therapy. The versatility
of this polypeptide sequence, which is compatible with various metal
ions and functional ligands, paves the way for a broad spectrum of
therapeutic and diagnostic applications.