Payne G A, Nierman W C, Wortman J R, Pritchard B L, Brown D, Dean R A, Bhatnagar D, Cleveland T E, Machida Masayuki, Yu J
Department of Plant Pathology, North Carolina State University, Raleigh, NC, USA.
The Institute for Genomic Research, Rockville, MD, USA.
Med Mycol. 2006 Sep 1;44(Supplement_1):S9-S11. doi: 10.1080/13693780600835716.
Aspergillus flavus is a plant and animal pathogen that also produces the potent carcinogen aflatoxin. Aspergillus oryzae is a closely related species that has been used for centuries in the food fermentation industry and is Generally Regarded As Safe (GRAS). Whole genome sequences for these two fungi are now complete, providing us with the opportunity to examine any genomic differences that may explain the different ecological niches of these two fungi, and perhaps to identify pathogenicity factors in A. flavus. These two fungi are very similar in genome size and number of predicted genes. The estimated genome size (36·8 Mb) and predicted number of genes (12 197) for A. flavus is similar to that of A. oryzae (36·7 Mb and 12 079, respectively). These two fungi have significantly larger genomes than Aspergillus nidulans (30·1) and Aspergillus fumigatus (29·4). The A. flavus and A. oryzae genomes are enriched in genes for secondary metabolism, but do not differ greatly from one another in the predicted number of polyketide synthases, nonribosomal peptide synthases or the number of genes coding for cytochrome P450 enzymes. A micro-scale analysis of the two fungi did show differences in DNA correspondence between the two species and in the number of transposable elements. Each species has approximately 350 unique genes. The high degree of sequence similarity between the two fungi suggests that they may be ecotypes of the same species and that A. oryzae has resulted from the domestication of A. flavus.
黄曲霉是一种动植物病原体，还能产生强效致癌物黄曲霉毒素。米曲霉是与之密切相关的一个物种，在食品发酵行业已被使用了几个世纪，并且被普遍认为是安全的（GRAS）。这两种真菌的全基因组序列现已完成，这使我们有机会研究可能解释这两种真菌不同生态位的任何基因组差异，或许还能鉴定出黄曲霉中的致病因子。这两种真菌在基因组大小和预测基因数量方面非常相似。黄曲霉的估计基因组大小（36.8 Mb）和预测基因数量（12197个）与米曲霉的相似（分别为36.7 Mb和12079个）。这两种真菌的基因组明显大于构巢曲霉（30.1 Mb）和烟曲霉（29.4 Mb）。黄曲霉和米曲霉的基因组富含次生代谢相关基因，但在聚酮合酶、非核糖体肽合成酶的预测数量或编码细胞色素P450酶的基因数量方面彼此差异不大。对这两种真菌的微观分析确实显示出这两个物种之间在DNA对应性和转座元件数量上存在差异。每个物种大约有350个独特基因。这两种真菌之间高度的序列相似性表明它们可能是同一物种的生态型，并且米曲霉是黄曲霉驯化的结果。
