Chiba Takashi, Takahashi Yumi, Sadamasu Kenji, Nakama Akiko, Kai Akemi
Department of Microbiology, Tokyo Metropolitan Institute of Public Health.
Shokuhin Eiseigaku Zasshi. 2014;55(3):135-41. doi: 10.3358/shokueishi.55.135.
We describe a simple method for discrimination of Aspergillus flavus group fungi, including aflatoxin (AF) producers, by means of molecular-biological analysis of 45 strains of A. flavus. First, 20 strains of A. flavus were compared using phylogenetic tree analysis based on the nucleotide sequences of ITS 1-5.8S-ITS 2 (ITS-1/2) and aflR-aflJ intergenic spacer (aflR/J-IGS). In this analysis, the tested strains were discriminated into 4 groups at the aflR/J-IGS region. Although ITS-1/2 region analysis could not discriminate between A. flavus (AF producers) and A. oryzae/A. flavus (AF nonproducers), aflR/J-IGS region analysis could discriminate between these groups. Moreover, 45 strains of A. flavus were compared by means of both phylogenetic tree analysis based on the aflR/J-IGS region and the conventional aflatoxin production test (culture method). The phylogenetic tree analysis of the tested strains was consistent with the findings of the culture method. In addition, 49 strains of A. flavus and related species (Aspergillus spp.) were tested by multiplex PCR with primers designed on the basis of the phylogenetic tree analysis. These results were consistent with phylogenetic tree analysis based on the aflR/J-IGS region for 41 strains.
我们描述了一种通过对45株黄曲霉进行分子生物学分析来鉴别黄曲霉群真菌（包括产黄曲霉毒素的菌株）的简单方法。首先，基于ITS 1-5.8S-ITS 2（ITS-1/2）和aflR-aflJ基因间隔区（aflR/J-IGS）的核苷酸序列，使用系统发育树分析对20株黄曲霉进行了比较。在该分析中，受试菌株在aflR/J-IGS区域被分为4组。虽然ITS-1/2区域分析无法区分黄曲霉（产黄曲霉毒素菌株）和米曲霉/黄曲霉（不产黄曲霉毒素菌株），但aflR/J-IGS区域分析能够区分这些组。此外，通过基于aflR/J-IGS区域的系统发育树分析和传统的黄曲霉毒素生产试验（培养法）对45株黄曲霉进行了比较。受试菌株的系统发育树分析结果与培养法的结果一致。此外，使用基于系统发育树分析设计的引物，通过多重PCR对49株黄曲霉及相关物种（曲霉属）进行了检测。对于41株菌株，这些结果与基于aflR/J-IGS区域的系统发育树分析结果一致。
