Nyaruaba, R. | Search bioRxiv

bioRxiv2026

Engineering Dual-Target Chimeric Lysins for Synergistic Eradication of Porphyromonas gingivalis

Periodontitis is a chronic inflammatory disease driven by complex subgingival multispecies biofilms, in which Porphyromonas gingivalis plays a central role in coordinating microbial interactions. Together with host-associated factors, these microbial communities create dual constraints that limit antimicrobial efficacy. In this study, we engineered a library of recombinant lysins by fusing membrane-destabilizing peptides to the periodontal pathogen-derived lysin LysPd078 and identified four optimized variants (PlyPd06, PlyPd19, PlyPd27, and PlyPd44) with enhanced salt tolerance, environmental stability, and bactericidal activity. In a clinically derived polymicrobial oral biofilm, PlyPd44 at only 25 g/mL eradicated 96.6% of P. gingivalis. In a humanized oral microbiota mouse model of periodontitis, selected PlyPds significantly reduced inflammation and inhibited alveolar bone loss compared with LysPd078 and minocycline. Collectively, these results establish membrane-destabilizing peptide-enabled lysins as a promising platform for developing microenvironment-adapted precision antimicrobials for periodontitis.

microbiology↗

bioRxiv2026

Structure-based similarity network accelerates the discovery of lysins as oral microbiome modulators targeting periodontal pathogens

Microorganisms significantly influence human health, and dysbiosis of the oral microbiome plays a critical role in the development and progression of both oral and systemic diseases. This highlights the urgent need for novel therapeutics targeting specific pathogens. Here, we presented a structure-based pipeline to efficiently identify potential phage-derived periodontal lysins (LysPds) from nearly one million proteins. We predicted the structures of candidate lysins using AlphaFold2 and developed an innovative structure-based similarity network to classify them into distinct clusters, each with unique functional properties. A systematic characterization of 16 representative LysPds from 11 superfamilies revealed that over 90% demonstrated potent antibacterial activity against key periodontal pathogens. Among these, LysPd078 was identified as a promising preclinical drug candidate, effectively reconfiguring microbiome communities while demonstrating significant efficacy and safety in mouse models of periodontitis and calvarial infection. Our findings highlight the effectiveness of structure-based similarity networks in exploring vast protein spaces and underscore the potential of LysPd078 as a targeted modulating agent for the oral microbiome.

microbiology↗