Entry exclusion enables selective conjugative DNA delivery in synthetic bacterial communities
Year: 2026
Type: preprint
Abstract: ABSTRACT Selective DNA delivery to specific members of assembled bacterial communities remains challenging. Bacterial conjugation enables efficient DNA delivery, but transfer to non-target recipients limits its specificity within mixed communities. Here, we repurpose plasmid entry exclusion (Eex) as a recipient-side gate to control conjugative DNA delivery. We demonstrate selective plasmid delivery to Eex-negative recipients within populations containing both Eex-expressing and Eex-negative cells. This recipient selectivity was maintained at increased cell densities and during prolonged mating. By combining RP4-type and F-type conjugation systems with their corresponding exclusion modules, we further directed DNA delivery from distinct donors to defined recipient populations. RP4-derived Eex also functioned in environmental bacteria, including Pseudomonas putida and Sphingobium japonicum , enabling recipient-specific exclusion within a multispecies mixture. Furthermore, repeated cycles of Eex-guided conjugation and selection altered community composition after assembly. These results establish entry exclusion as a recipient-side strategy for selective conjugative DNA delivery and, when combined with selection, for controlling the composition of assembled bacterial communities. GRAPHICAL ABSTRACT
Institution: Tohoku University
Language: English
Subfield: Genetics
Domain: Life Sciences
Open Access status: green
Awards: Reconstruction of ancestral plasmid conjugation systems and identification of conjugation-inhibiting and promoting compounds, Construction and Application of a Chromosome-Independent Plasmid Conjugative Transfer System, G5853934712, Programmable Bacterial Adhesion Modules for Broad-Spectrum Applications, Advancing Bioremediation Utilizing Cell-Cell Adhesion Enhancement Systems
OpenAlex ID: W7214311155