A sensitive and inexpensive yeast bioassay for the mycotoxin zearalenone and other compounds with estrogenic activity
A sensitive and inexpensive yeast bioassay for the mycotoxin zearalenone and other compounds with estrogenic activity
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DOI：
10.1128/aem.69.2.805-811.2003
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发表时间：
2003-02-01
影响因子：
4.4
通讯作者：
Adam, G
中科院分区：
文献类型：
--
作者：
Mitterbauer, R;Weindorfer, H;Adam, G
玉米赤霉烯酮（ZON）是一种由植物病原镰刀菌产生的非甾体类雌激素毒素。由于感染了黄色镰刀菌和禾谷镰刀菌，ZON可以在谷物和衍生食品中发现。由于ZON被怀疑是人类疾病的原因，包括早熟综合征，以及农场动物的雌激素过多症，一些国家已经建立了用于人类消费和动物饲料的谷物中ZON水平的监测计划和指南。我们开发了一种低成本的方法来监测ZON污染的粮食敏感的酵母生物测定的基础上。指示剂酿酒酵母菌株YZRM 7不能生长，除非在外源性雌激素物质存在下通过表达的人雌激素受体激活工程化嘧啶生物合成基因。缺失编码ATP结合盒（ABC）转运蛋白Pdr5p和Snq2p的基因协同地增加净ZON摄取。每升培养基中少于1 μ g的ZON足以使指示菌株生长。为了防止干扰生物样品中可能存在的嘧啶，我们还破坏了基因FUR1和URK1，阻断了嘧啶补救途径。生物测定菌株YZRM 7允许定性检测和定量谷物提取物中的总雌激素活性，而不需要进一步的净化步骤。它的高灵敏度，使该测定适合于低成本的监测污染的玉米和小谷物与雌激素镰刀菌毒素。
Zearalenone (ZON) is a nonsteroidal estrogenic mycotoxin produced by plant-pathogenic species of Fusarium. As a consequence of infection with Fusarium culmorum and Fusarium graminearum, ZON can be found in cereals and derived food products. Since ZON is suspected to be, a cause of human disease, including premature puberty syndrome, as well as hyperestrogenism in farm animals, several countries have established monitoring programs and guidelines for ZON levels in grain intended for human consumption and animal feed. We developed a low-cost method for monitoring ZON contamination in grain based on a sensitive yeast bioassay. The indicator Saccharomyces cerevisiae strain YZRM7 is unable to grow unless an engineered pyrimidine biosynthetic gene is activated by the expressed human estrogen receptor in the presence of exogenous estrogenic substances. Deletion of the genes encoding ATP-binding cassette (ABC) transporters Pdr5p and Snq2p increases net ZON uptake synergistically. Less than 1 mug of ZON per liter of medium is sufficient to allow growth of the indicator strain. To prevent interference with pyrimidines potentially present in biological samples, we also disrupted the genes FUR1 and URK1, blocking the pyrimidine salvage pathway. The bioassay strain YZRM7 allows qualitative detection and quantification of total estrogenic activity in cereal extracts without requiring further cleanup steps. Its high sensitivity makes this assay suitable for low-cost monitoring of contamination of maize and small grain cereals with estrogenic Fusarium mycotxins.