Genomic sequence of the aflatoxigenic filamentous fungus Aspergillus nomius

BMC Genomics

Shannon B. Beltz¹  Brian M. Mack¹  Geromy G. Moore¹ 

[1] United States Department of Agriculture, Agricultural Research Service, Southern Regional Research Center, New Orleans, LA, USA

关键词: Mating-type locus;    Phylogenomics;    Gene ontology;    Genome sequence;    Aspergillus nomius;   

Others  :  1221853
DOI  :  10.1186/s12864-015-1719-6

 received in 2014-12-30, accepted in 2015-06-25,  发布年份 2015

【 摘 要 】

Background

Aspergillus nomius is an opportunistic pathogen and one of the three most important producers of aflatoxins in section Flavi. This fungus has been reported to contaminate agricultural commodities, but it has also been sampled in non-agricultural areas so the host range is not well known. Having a similar mycotoxin profile as A. parasiticus, isolates of A. nomius are capable of secreting B- and G- aflatoxins.

Results

In this study we discovered that the A. nomius type strain (NRRL 13137) has a genome size of approximately 36 Mb which is comparable to other Aspergilli whose genomes have been sequenced. Its genome encompasses 11,918 predicted genes, 72 % of which were assigned GO terms using BLAST2GO. More than 1,200 of those predicted genes were identified as unique to A. nomius, and the most significantly enriched GO category among the unique genes was oxidoreducatase activity. Phylogenomic inference shows NRRL 13137 as ancestral to the other aflatoxigenic species examined from section Flavi. This strain contains a single mating-type idiomorph designated as MAT1-1.

Conclusions

This study provides a preliminary analysis of the A. nomius genome. Given the recently discovered potential for A. nomius to undergo sexual recombination, and based on our findings, this genome sequence provides an additional evolutionary reference point for studying the genetics and biology of aflatoxin production.

【 授权许可】

   
2015 Moore et al.

【 图 表 】

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