Nanduri Viswaprakash, Bhunia Arun K, Tu Shu-I, Paoli George C, Brewster Jeffrey D
Center For Food Safety and Engineering, Department of Food Science, Purdue University, 745 Agriculture Mall Dr., West Lafayette, IN 47907, USA.
Biosens Bioelectron. 2007 Sep 30;23(2):248-52. doi: 10.1016/j.bios.2007.04.007. Epub 2007 Apr 19.
Whole cells of Listeria monocytogenes were detected with a compact, surface plasmon resonance (SPR) sensor using a phage-displayed scFv antibody to the virulence factor actin polymerization protein (ActA) for biorecognition. Phage Lm P4:A8, expressing the scFv antibody fused to the pIII surface protein was immobilized to the sensor surface through physical adsorption. A locally constructed fluidics system was used to deliver solutions to the compact, two-channel SPREETA sensor. Specificity of the sensor was tested using common food-borne bacteria and a control phage, M13K07 lacking the scFv fusion on its coat protein. The detection limit for L. monocytogenes whole cells was estimated to be 2 x 10(6)cfu/ml. The sensor was also used to determine the dissociation constant (Kd) for the interaction of phage-displayed scFv and soluble ActA in solution as 4.5 nM.
利用一种针对毒力因子肌动蛋白聚合蛋白（ActA）的噬菌体展示单链抗体片段（scFv）进行生物识别，通过紧凑型表面等离子体共振（SPR）传感器检测单核细胞增生李斯特菌的全细胞。表达与pIII表面蛋白融合的scFv抗体的噬菌体Lm P4:A8通过物理吸附固定在传感器表面。使用本地构建的流体系统将溶液输送到紧凑型双通道SPREETA传感器。使用常见食源细菌和一种对照噬菌体M13K07（其外壳蛋白上缺乏scFv融合）测试传感器的特异性。单核细胞增生李斯特菌全细胞的检测限估计为2×10⁶cfu/ml。该传感器还用于确定溶液中噬菌体展示的scFv与可溶性ActA相互作用的解离常数（Kd）为4.5 nM。
