Biosciences, Council for Scientific and Industrial Research (CSIR), Brummeria, Pretoria, South Africa.
BMC Microbiol. 2010 Mar 23;10:87. doi: 10.1186/1471-2180-10-87.
Mycotoxins are secondary metabolites which are produced by numerous fungi and pose a continuous challenge to the safety and quality of food commodities in South Africa. These toxins have toxicologically relevant effects on humans and animals that eat contaminated foods. In this study, a diagnostic DNA microarray was developed for the identification of the most common food-borne fungi, as well as the genes leading to toxin production.
A total of 40 potentially mycotoxigenic fungi isolated from different food commodities, as well as the genes that are involved in the mycotoxin synthetic pathways, were analyzed. For fungal identification, oligonucleotide probes were designed by exploiting the sequence variations of the elongation factor 1-alpha (EF-1 alpha) coding regions and the internal transcribed spacer (ITS) regions of the rRNA gene cassette. For the detection of fungi able to produce mycotoxins, oligonucleotide probes directed towards genes leading to toxin production from different fungal strains were identified in data available in the public domain. The probes selected for fungal identification and the probes specific for toxin producing genes were spotted onto microarray slides.
The diagnostic microarray developed can be used to identify single pure strains or cultures of potentially mycotoxigenic fungi as well as genes leading to toxin production in both laboratory samples and maize-derived foods offering an interesting potential for microbiological laboratories.
真菌毒素是由多种真菌产生的次生代谢物，对南非食品商品的安全和质量构成持续挑战。这些毒素对食用受污染食物的人类和动物具有毒理学相关影响。在这项研究中，开发了一种诊断 DNA 微阵列，用于鉴定最常见的食源性真菌以及导致毒素产生的基因。
分析了从不同食品商品中分离出的总共 40 种潜在产毒真菌，以及参与真菌毒素合成途径的基因。为了进行真菌鉴定，通过利用延伸因子 1-α（EF-1α）编码区和 rRNA 基因盒的内部转录间隔区（ITS）区的序列变异来设计寡核苷酸探针。为了检测能够产生真菌毒素的真菌，在公共领域中可用的数据库中鉴定了针对来自不同真菌菌株的毒素产生基因的寡核苷酸探针。选择用于真菌鉴定的探针和用于毒素产生基因的探针特异性地在微阵列载玻片上进行斑点杂交。
开发的诊断微阵列可用于鉴定单一纯菌株或培养物的潜在产毒真菌以及实验室样品和玉米衍生食品中导致毒素产生的基因，为微生物学实验室提供了有趣的潜力。
