Artificially Engineered Protein as Material Platform for Antimicrobial Peptides

Many of the more than 3000 antimicrobial peptides (AMPs) that have been identified are considered promising alternatives to existing antibiotic, antiviral, and antifungal drugs to treat antimicrobial resistant infections. However, the clinical implementation of AMPs remains limited by their low <i>in vivo</i> efficacy, compared to <i>in vitro </i>activity, due to their vulnerability to protease/enzyme degradation and renal filtration. AMPs that are tethered to biomaterial surfaces are resistant to the filtration barrier by increasing the size of the material system and to the protease degradation due to physicochemical properties of macromolecular tethers. Yet, tethering AMPs typically comes at the cost of reduced potency, and challenges for conventional AMP-incorporated materials include ensuring the consistent synthesis of each material component, reproducible conjugation efficiency with high yields for reliable experimental results, and the flexibility to precisely modulate design parameters. Overcoming these challenges will jumpstart investigations of AMP-incorporated biomaterials to establish more informed design principles for advanced AMP therapeutics.<br/><br/>Here, we developed an AMP-incorporated material platform that simplifies manufacturing for high reproducibility and enables a systematic investigation of design parameters to potentially permit the utilization of many unique AMPs with improved potency. Our approach is an artificial protein platform, comprised of an AMP, a protein tether, and a material-forming protein as a modifiable biomaterial scaffold for various clinical applications. We biosynthesized the artificial proteins in high yields with reproducibility and fabricated strength-controllable, cytocompatible hydrogels and temperature-responsive, self-assembled micelles. We also validated developed materials to inhibit bacterial growth. Since the biosynthesis of artificial proteins is reproducible, and scalable, we expect that there is significant potential of the AMP-incorporated materials for clinical translation. Furthermore, the results will lead future studies to develop an artificial protein-based biomaterial platform for diverse AMPs, as well as a combinatorial approach that mixes several different AMPs into one material as an effective wide-reaching therapeutic strategy to treat a broad range of microbial infections.