Food and Feed Safety Unit, USDA, New Orleans, Louisiana, United States of America.
The J. Craig Venter Institute, Rockville, Maryland, United States of America.
PLoS One. 2018 Jul 2;13(7):e0199169. doi: 10.1371/journal.pone.0199169. eCollection 2018.
Aspergillus flavus is a saprophytic fungus that infects corn, peanuts, tree nuts and other agriculturally important crops. Once the crop is infected the fungus has the potential to secrete one or more mycotoxins, the most carcinogenic of which is aflatoxin. Aflatoxin contaminated crops are deemed unfit for human or animal consumption, which results in both food and economic losses. Within A. flavus, two morphotypes exist: the S strains (small sclerotia) and L strains (large sclerotia). Significant morphological and physiological differences exist between the two morphotypes. For example, the S-morphotypes produces sclerotia that are smaller (< 400 μm), greater in quantity, and contain higher concentrations of aflatoxin than the L-morphotypes (>400 μm). The morphotypes also differ in pigmentation, pH homeostasis in culture and the number of spores produced. Here we report the first full genome sequence of an A. flavus S morphotype, strain AF70. We provide a comprehensive comparison of the A. flavus S-morphotype genome sequence with a previously sequenced genome of an L-morphotype strain (NRRL 3357), including an in-depth analysis of secondary metabolic clusters and the identification SNPs within their aflatoxin gene clusters.
黄曲霉是一种腐生真菌，可感染玉米、花生、坚果和其他重要农作物。一旦作物受到感染，真菌就有可能分泌一种或多种霉菌毒素，其中最具致癌性的是黄曲霉毒素。受黄曲霉毒素污染的作物不适合人类或动物食用，这会导致食物和经济损失。在黄曲霉中，存在两种形态型：S 菌株（小菌核）和 L 菌株（大菌核）。这两种形态型在形态和生理上存在显著差异。例如，S 形态型产生的菌核较小（<400μm）、数量更多，且黄曲霉毒素浓度高于 L 形态型（>400μm）。形态型在色素沉着、培养中的 pH 稳态以及产生的孢子数量上也存在差异。在这里，我们报告了第一个黄曲霉 S 形态型菌株 AF70 的全基因组序列。我们对黄曲霉 S 形态型基因组序列与之前测序的 L 形态型菌株（NRRL 3357）进行了全面比较，包括对次生代谢物簇的深入分析以及鉴定其黄曲霉毒素基因簇中的单核苷酸多态性。
