Development of Synthetic Antimicrobial Peptides Based on Genomic Analysis of Streptococcus salivarius

In the oral environment, the production of bacteriocins or antimicrobial peptides (AMPs) plays a crucial role in maintaining ecological balance by impeding the proliferation of closely related microorganisms. This study aims to conduct in silico genome screening of Streptococcus salivarius to identify potential antimicrobial compounds existing as hypothetical peptides, with the goal of developing novel synthetic antimicrobial peptides.

Draft genomes of various oral Streptococcus salivarius strains were obtained from the NCBI database and subjected to analysis using bioinformatic tools, viz. Expert Protein-Analysis System (Expasy), UniProt Knowledgebase (UniProtKB), European Molecular Biology Open Software Suite (EMBOSS), Pepwheel, and PEP-FOLD Peptide Structure Prediction Server. The antimicrobial potential of peptides was assessed through the Antimicrobial Peptide Database (AMP) and Bactibase. Two short peptides, viz. synthetic antimicrobial peptides (SAMPs), were designed based on current knowledge of hydrophobic and cationic residues, synthesized, and their efficacy against biofilm formation was evaluated with standard microbiological methods.

The synthesized short peptides reduced the growth and effectively inhibited biofilm formation by specific oral microbial strains, demonstrating their potential as antimicrobial peptides. Furthermore, the alignment of bacteriocin biosynthetic clusters among streptococcus strains revealed variations in putative bacteriocin amino acid sequences across different strains of the same organism.

Streptococcus salivarius emerges as a promising bioresource for the development of novel antimicrobial agents, particularly for combating biofilm-associated oral infections.