Key Laboratory of Special Pathogens and Biosafety, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, Hubei 430071, PR China; University of Chinese Academy of Sciences, Beijing 100039, PR China.
Key Laboratory of Special Pathogens and Biosafety, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan, Hubei 430071, PR China; University of Chinese Academy of Sciences, Beijing 100039, PR China; Henan Collaborative Innovation Center of Molecular Diagnosis and Laboratory Medicine, School of Laboratory Medicine, Xinxiang Medical University, Xinxiang, Henan 453003, PR China.
Talanta. 2017 Aug 1;170:291-297. doi: 10.1016/j.talanta.2017.04.007. Epub 2017 Apr 4.
A Staphylococcus aureus (S. aureus)-specific lytic bacteriophage P-S. aureus-9, isolated from an environmental water sample, was assembled on magnetic beads for capturing S. aureus from samples through magnetic separation. Horseradish Peroxidase (HRP) labeled immunoglobulin (IgG) antibodies were used to detect the captured S. aureus by reacting with protein A on S. aureus followed by colorimetric signals, which were generated from the catalytic reaction between HRP and the substrate 3,3',5,5'-Tetramethylbenzidine (TMB). Under optimal conditions, the calibration curve was linear from 1.0×10 to 1.0×10CFUmL. The limit of detection (LOD) for the assay was 2.47×10CFUmL and 8.86×10CFUmL of S. aureus in PBS and apple juice, respectively. Moreover, the whole assay revealed outstanding specificity towards S. aureus, without any interference of common pathogenic bacteria, and can be completed within 90min without any pre-enrichment. As far as known, it was the first time to detect S. aureus based on the double site recognition of bacteriophage and mammal IgG. The novel approach has shown good potentials for a rapid, specific, cheap and simple detection of S. aureus in food samples.
从环境水样中分离到一株金黄色葡萄球菌（S. aureus）特异性裂解噬菌体 P-S. aureus-9，将其组装到磁珠上，通过磁分离从样品中捕获 S. aureus。辣根过氧化物酶（HRP）标记的免疫球蛋白（IgG）抗体与 S. aureus 上的蛋白 A 反应，检测被捕获的 S. aureus，随后产生比色信号，该信号由 HRP 和底物 3,3',5,5'-四甲基联苯胺（TMB）之间的催化反应产生。在最佳条件下，校准曲线在 1.0×10 至 1.0×10CFUmL 之间呈线性。该测定法的检测限（LOD）分别为 PBS 和苹果汁中的 2.47×10CFUmL 和 8.86×10CFUmL 的 S. aureus。此外，整个检测方法对 S. aureus 具有出色的特异性，没有任何常见致病菌的干扰，并且无需预富集即可在 90min 内完成。据所知，这是首次基于噬菌体和哺乳动物 IgG 的双位点识别来检测 S. aureus。该新方法在食品样品中快速、特异性、廉价和简单地检测 S. aureus 方面显示出良好的潜力。
