Institute of Molecular Biology, Academia Sinica, Taipei, Taiwan.
Molecular and Cell Biology, Taiwan International Graduate Program, Academia Sinica and National Defense Medical Center, Taipei, Taiwan.
Nat Commun. 2024 Aug 3;15(1):6568. doi: 10.1038/s41467-024-51017-1.
Developing programmable bacterial cell-cell adhesion is of significant interest due to its versatile applications. Current methods that rely on presenting cell adhesion molecules (CAMs) on bacterial surfaces are limited by the lack of a generalizable strategy to identify such molecules targeting bacterial membrane proteins in their natural states. Here, we introduce a whole-cell screening platform designed to discover CAMs targeting bacterial membrane proteins within a synthetic bacteria-displayed nanobody library. Leveraging the potency of the bacterial type IV secretion system-a contact-dependent DNA delivery nanomachine-we have established a positive feedback mechanism to selectively enrich for bacteria displaying nanobodies that target antigen-expressing cells. Our platform successfully identified functional CAMs capable of recognizing three distinct outer membrane proteins (TraN, OmpA, OmpC), demonstrating its efficacy in CAM discovery. This approach holds promise for engineering bacterial cell-cell adhesion, such as directing the antibacterial activity of programmed inhibitor cells toward target bacteria in mixed populations.
由于其广泛的应用，开发可编程的细菌细胞间黏附具有重要意义。目前依赖于在细菌表面呈现细胞黏附分子（CAM）的方法受到缺乏通用策略的限制，无法识别天然状态下针对细菌膜蛋白的此类分子。在这里，我们引入了一种全细胞筛选平台，旨在从合成的细菌展示纳米体文库中发现针对细菌膜蛋白的 CAM。利用细菌 IV 型分泌系统（一种接触依赖性 DNA 输送纳米机器）的强大功能，我们建立了一种正反馈机制，用于选择性富集针对表达抗原的细胞的纳米体。我们的平台成功鉴定了能够识别三种不同外膜蛋白（TraN、OmpA、OmpC）的功能性 CAM，证明了其在 CAM 发现中的功效。这种方法有望用于工程细菌细胞间黏附，例如将编程抑制剂细胞的抗菌活性引导至混合群体中的目标细菌。
