Molecular Characterization of Foodborne Pathogens Research Unit, US Department of Agriculture, Agricultural Research Service, Eastern Regional Research Center (USDA-ARS-ERRC), 600 East Mermaid Lane, Wyndmoor, PA 19038, USA.
Molecular Characterization of Foodborne Pathogens Research Unit, US Department of Agriculture, Agricultural Research Service, Eastern Regional Research Center (USDA-ARS-ERRC), 600 East Mermaid Lane, Wyndmoor, PA 19038, USA.
Food Microbiol. 2015 May;47:28-35. doi: 10.1016/j.fm.2014.11.004. Epub 2014 Nov 15.
Campylobacter jejuni and Campylobacter coli are the two important species responsible for most of the Campylobacter infections in humans. Reliable isolation and detection of Campylobacter spp. from food samples are challenging due to the interferences from complex food substances and the fastidious growth requirements of this organism. In this study, a novel biosensor-based detection called BARDOT (BActerial Rapid Detection using Optical scattering Technology) was developed for high-throughput screening of Campylobacter colonies grown on an agar plate without disrupting the intact colonies. Image pattern characterization and principal component analysis (PCA) of 6909 bacterial colonies showed that the light scatter patterns of C. jejuni and C. coli were strikingly different from those of Salmonella spp., Escherichia coli O157:H7, and Listeria monocytogenes. Examination of a mixed culture of these microorganisms revealed 85% (34/40) accuracy in differentiating Campylobacter from the other three major foodborne pathogens based on the similarity to the scatter patterns in an established library. The application of BARDOT in real food has been addressed through the analysis of Campylobacter spiked ground chicken and naturally contaminated fresh chicken pieces. Combined with real-time PCR verification, BARDOT was able to identify Campylobacter isolates from retail chicken. Moreover, applying passive filtration to food samples facilitated the isolation of pure Campylobacter colonies and therefore overcame the interference of the food matrix on BARDOT analysis.
空肠弯曲菌和大肠弯曲菌是导致人类大多数弯曲菌感染的两种重要物种。由于复杂的食物物质的干扰和该生物体的苛刻生长要求，可靠地从食物样本中分离和检测弯曲菌属是具有挑战性的。在本研究中，开发了一种称为 BARDOT（使用光学散射技术的细菌快速检测）的新型基于生物传感器的检测方法，用于在不破坏完整菌落的情况下对琼脂平板上生长的弯曲菌菌落进行高通量筛选。6909 个细菌菌落的图像模式特征和主成分分析（PCA）表明，空肠弯曲菌和大肠弯曲菌的光散射模式与沙门氏菌属、大肠杆菌 O157:H7 和单核细胞增生李斯特菌的光散射模式明显不同。对这些微生物的混合培养物的检查表明，基于与已建立的库中的散射模式的相似性，BARDOT 在区分弯曲菌与其他三种主要食源性病原体方面的准确率为 85%（34/40）。通过对添加弯曲菌的鸡肉和受污染的新鲜鸡肉块的分析，已经解决了 BARDOT 在实际食品中的应用问题。结合实时 PCR 验证，BARDOT 能够从零售鸡肉中识别弯曲菌分离株。此外，通过对食物样本进行被动过滤，有利于分离出纯弯曲菌菌落，从而克服了食物基质对 BARDOT 分析的干扰。
