Department of Microbiology, Pusan National University, 2 Busandaehak-ro 63 Beon-gil, Geumjeong-gu, Busan, Republic of Korea.
Department of Fine Chemistry, Seoul National University of Science and Technology, 232 Gongneung-ro, Nowon-gu, Seoul, Republic of Korea.
J Hazard Mater. 2024 Oct 5;478:135463. doi: 10.1016/j.jhazmat.2024.135463. Epub 2024 Aug 9.
Enterococci are common indicators of fecal contamination and are used to assess the quality of fresh and marine water, sand, soil, and sediment. However, samples collected from these environments contain various cells and other factors that can interfere with the assays used to detect enterococci. We developed a novel assay for the sensitive and specific detection of enterococci that is resistant to interference from other cells and environmental factors. Our interference-resistant assay used 30-nm gold nanoparticles (AuNPs), streptavidin, and a biotinylated Enterococcus antibody. Enterococci inhibited the interaction between streptavidin and biotin and led to the disaggregation of AuNPs. The absence of enterococci led to the aggregation of AuNPs, and this difference was easily detected by spectrophotometry. This interference-resistant AuNP assay was able to detect whole cells of Enterococcus in the range of 10 to 10 CFU/mL within 3 h, had high specificity for enterococci, and was unaffected by the presence of other intestinal bacteria, such as Escherichia coli. Our examination of fresh and marine water samples demonstrated no interference from other cells or environmental factors. The interference-resistant AuNP assay described here has the potential to be used as a rapid, simple, and effective method for monitoring enterococci in diverse environmental samples.
肠球菌是粪便污染的常见指示菌，用于评估淡水和海水、沙子、土壤和沉积物的质量。然而，从这些环境中采集的样本含有各种细胞和其他因素，可能会干扰用于检测肠球菌的检测方法。我们开发了一种新的检测方法，用于灵敏和特异性地检测肠球菌，该方法能够抵抗来自其他细胞和环境因素的干扰。我们的抗干扰检测方法使用了 30nm 金纳米颗粒（AuNPs）、链霉亲和素和生物素化肠球菌抗体。肠球菌抑制了链霉亲和素和生物素之间的相互作用，导致 AuNPs 解聚。不存在肠球菌则导致 AuNPs 聚集，这种差异可以通过分光光度法轻松检测到。这种抗干扰的 AuNP 检测法能够在 3 小时内检测到 10 到 10 CFU/mL 范围内的肠球菌全细胞，对肠球菌具有高度特异性，并且不受其他肠道细菌（如大肠杆菌）的影响。我们对淡水和海水样本的检查表明，没有其他细胞或环境因素的干扰。本文描述的抗干扰 AuNP 检测法有可能成为监测各种环境样本中肠球菌的快速、简单和有效的方法。
