The genus Listeria comprises ubiquitous bacteria, commonly present in foods and food production facilities. In this study, three different phage display technologies were employed to discover targets, and to generate and characterize novel antibodies against Listeria: antibody display for biomarker discovery and antibody generation; ORFeome display for target identification; and single-gene display for epitope characterization. With this approach, pyruvate dehydrogenase complex—enzyme 2 (PDC-E2) was defined as a new detection target for Listeria, as confirmed by immunomagnetic separation-mass spectrometry (IMS-MS). Immunoblot and fluorescence microscopy showed that this protein is accessible on the bacterial cell surface of living cells. Recombinant PDC-E2 was produced in E. coli and used to generate 16 additional antibodies. The resulting set of 20 monoclonal scFv-Fc was tested in indirect ELISA against 17 Listeria and 16 non-Listeria species. Two of them provided 100% sensitivity (CI 82.35–100.0%) and specificity (CI 78.20–100.0%), confirming PDC-E2 as a suitable target for the detection of Listeria. The binding region of 18 of these antibodies was analyzed, revealing that ≈ 90% (16/18) bind to the lipoyl domains (LD) of the target. The novel target PDC-E2 and highly specific antibodies against it offer new opportunities to improve the detection of Listeria.

属李斯特菌包括无处不在的细菌，通常存在于食品和食品生产设施。在这项研究中，采用了三种不同的噬菌体展示技术来发现靶标，并生成和表征针对李斯特菌的新型抗体：用于生物标志物发现和抗体生成的抗体展示；用于目标识别的 ORFeome 显示；和用于表位表征的单基因展示。通过这种方法，丙酮酸脱氢酶复合物酶 2 (PDC-E2) 被定义为李斯特菌的新检测目标，正如免疫磁性分离质谱法 (IMS-MS) 所证实的那样。免疫印迹和荧光显微镜显示该蛋白质可在活细胞的细菌细胞表面上接触。重组 PDC-E2 在大肠杆菌中产生并用于产生 16 种额外的抗体。在针对 17 种李斯特菌和 16种非李斯特菌种类的间接 ELISA 中测试了所得的 20 个单克隆 scFv-Fc 组。其中两个提供了 100% 的灵敏度 (CI 82.35–100.0%) 和特异性 (CI 78.20–100.0%)，证实 PDC-E2 是检测李斯特菌的合适靶点. 分析了这些抗体中 18 种的结合区，表明大约 90% (16/18) 结合到靶标的硫辛酰域 (LD)。新的目标 PDC-E2 和针对它的高度特异性抗体为改进李斯特菌检测提供了新的机会。