Blais B W, Leggate J, Bosley J, Martinez-Perez A
Ottawa Laboratory (Carling), Canadian Food Inspection Agency, CEF, Ottawa, Canada.
Lett Appl Microbiol. 2004;39(6):516-22. doi: 10.1111/j.1472-765X.2004.01616.x.
Different indicator enzymes and fluorogenic or chromogenic substrates were compared as detector systems in a novel polymyxin-based enzyme-linked immunosorbent assay (ELISA) for Escherichia coli O157 lipopolysaccharide (LPS) antigens.
An ELISA system was developed using polymyxin immobilized in the wells of a microtitre plate as a high-affinity adsorbent for E. coli O157 LPS antigens, which were immunoenzymatically detected using anti-E. coli O157 antibody-enzyme conjugates. With peroxidase as the indicator enzyme the fluorogenic substrates Amplex Red and QuantaBlu produced only slight improvement in the performance characteristics of the polymyxin-ELISA compared with the use of the chromogenic substrate tetramethylbenzidine (TMB). On the other hand, with alkaline phosphatase as the indicator enzyme a pronounced improvement in assay performance was noted using the fluorogenic substrate Attophos compared with the chromogenic substrate p-nitrophenylphosphate.
The detection system exhibiting the best characteristics with respect to cost, ease of use and overall performance in the detection of E. coli O157 in enrichment cultures from a variety of solid foods was based on the use of peroxidase as the indicator enzyme with the chromogenic substrate TMB.
The polymyxin-ELISA provides a rapid, simple and inexpensive assay system for the detection of E. coli O157 in foods.
在一种基于多粘菌素的新型酶联免疫吸附测定（ELISA）中，比较不同的指示酶以及荧光或显色底物作为大肠杆菌O157脂多糖（LPS）抗原检测系统。
开发了一种ELISA系统，使用固定在微量滴定板孔中的多粘菌素作为大肠杆菌O157 LPS抗原的高亲和力吸附剂，使用抗大肠杆菌O157抗体 - 酶偶联物进行免疫酶检测。以过氧化物酶作为指示酶时，与使用显色底物四甲基联苯胺（TMB）相比，荧光底物Amplex Red和QuantaBlu在多粘菌素 - ELISA性能特征上仅产生轻微改善。另一方面，以碱性磷酸酶作为指示酶时，与显色底物对硝基苯磷酸酯相比，使用荧光底物Attophos时检测性能有显著改善。
在检测来自各种固体食品的富集培养物中的大肠杆菌O157时，在成本、易用性和整体性能方面表现出最佳特征的检测系统是基于使用过氧化物酶作为指示酶和显色底物TMB。
多粘菌素 - ELISA为食品中大肠杆菌O157的检测提供了一种快速、简单且廉价的检测系统。
