Evaluating Host Defense Peptides: A Comparative Analysis of Synthetic Peptides and Recombinant Concatemers.

The global antibiotic resistance crisis raises concerns about antibiotic use, and alternative strategies are urgently needed. In this context, host defense peptides (HDPs) have rapidly gained interest. However, one of the main obstacles is their production strategy. Chemical synthesis is the most widely used, although it is not scalable and has sequence limitations. A possible alternative is recombinant production, but the strategies used so far have limited efficiency. In this study, we aim to compare the activity and main characteristics of different HDPs produced by both chemical synthesis and by recombinant production, using an approach based on tetramers to ameliorate the production process. The results obtained showed that the production of HDPs as tetrameric peptides by recombinant production in Lactococcus lactis enhanced the peptide activity, with HDPs being much more active in terms of antimicrobial activity, more structurally stable, and nanostructured. Thus, the recombinant strategy described herein, fusing four repetitions of the same peptide, can become a real alternative to produce highly active HDPs through a scalable production process.