Cyclophane-containing RiPPs targeting BamA for antibacterial applications

Overview

This research introduces a new class of ribosomally synthesized and posttranslationally modified peptides (RiPPs) featuring three-residue cyclophane rings. These rings constrain the peptide into a rigid beta-strand conformation, enabling it to bind BamA, an essential outer membrane protein required for outer membrane assembly in Gram-negative bacteria. Because BamA is critical for bacterial survival, targeting it represents a novel antibacterial mode of action. The analogues are unique among known cyclophane-containing peptides and are being investigated for activity against relevant plant pathogenic bacteria. These peptides have not been commercialized, positioning them as a differentiated platform for antimicrobial discovery.

Technical specifications

• Peptide class: Ribosomally synthesized and posttranslationally modified peptides (RiPPs), a class of natural-product-derived molecules produced through ribosomal gene expression followed by enzymatic modifications.
• Structural feature: Three-residue cyclophane rings that lock the peptide into a beta-strand conformation, providing conformational rigidity for target engagement.
• Molecular target: BamA, the central component of the BAM (beta-barrel assembly machinery) complex responsible for folding and inserting outer membrane proteins in Gram-negative bacteria.
• Differentiation: The analogues are structurally unique relative to previously characterized cyclophane-containing peptides, potentially enabling selectivity toward plant pathogenic strains.
• Mode of action: Disruption of outer membrane biogenesis through BamA binding, distinct from existing antibiotic classes and therefore potentially bypassing common resistance mechanisms.

Technology readiness level

The project is at an early discovery stage. The research team has established a structural rationale based on the known ability of cyclophane-containing peptides to bind BamA and has formulated a hypothesis that the new analogues can target plant pathogenic bacteria. Future validation will focus on confirming binding affinity to BamA, assessing antibacterial activity against relevant Gram-negative pathogens, and evaluating selectivity and potency. Commercial-scale production, formulation, and field validation studies have not yet been performed. The technology is positioned for early-stage collaboration with industry partners interested in novel antibacterial scaffolds for agricultural or therapeutic applications.