The major volatile compound 2-phenylethanol from the biocontrol yeast, Pichia anomala, inhibits growth and expression of aflatoxin biosynthetic genes of Aspergillus flavus
The major volatile compound 2-phenylethanol from the biocontrol yeast, Pichia anomala, inhibits growth and expression of aflatoxin biosynthetic genes of Aspergillus flavus
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DOI：
10.1007/s12550-014-0189-z
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发表时间：
2014-05-01
影响因子：
3
通讯作者：
Gee, Wai
中科院分区：
文献类型：
--
作者：
Hua, Sui Sheng T.;Beck, John J.;Gee, Wai
黄曲霉是一种普遍存在的腐生植物，能够产生最有效的天然致癌化合物黄曲霉毒素B-1 （AFB(1)）。这种毒素经常污染农作物，包括玉米、棉花、花生和坚果，在世界范围内造成巨大的经济损失。因此，100多个国家有严格的法规限制食品和饲料中的AFB(1)。植物和微生物能够产生挥发性化合物，作为对抗其他生物的防御机制。毕氏异常酵母菌WRL-076是一种生物防治酵母菌，目前正在测试以减少加州树坚果的AF污染。我们使用SPME-GC/MS分析，确定该菌株产生的主要挥发性化合物为2-苯乙醇（2-PE）。抑制黄曲霉孢子萌发和AF的产生。2-PE对房颤形成的抑制与聚集性房颤生物合成基因的显著下调相关，基因表达降低数倍至10000倍以上就是证据。在时间过程分析中，我们发现2-PE还改变了染色质修饰基因MYST1、MYST2、MYST3、gcn5、hdaA和rpdA的表达模式。黄曲霉的生物防治能力可能与2-PE的产生有关，2-PE影响黄曲霉孢子萌发、生长、毒素产生和基因表达。
Aspergillus flavus is a ubiquitous saprophyte that is able to produce the most potent natural carcinogenic compound known as aflatoxin B-1 (AFB(1)). This toxin frequently contaminates crops including corn, cotton, peanuts, and tree nuts causing substantial economic loss worldwide. Consequently, more than 100 countries have strict regulations limiting AFB(1) in foodstuffs and feedstuffs. Plants and microbes are able to produce volatile compounds that act as a defense mechanism against other organisms. Pichia anomala strain WRL-076 is a biocontrol yeast currently being tested to reduce AF contamination of tree nuts in California. We used the SPME-GC/MS analysis and identified the major volatile compound produced by this strain to be 2-phenylethanol (2-PE). It inhibited spore germination and AF production of A. flavus. Inhibition of AF formation by 2-PE was correlated with significant down regulation of clusteringAF biosynthesis genes as evidenced by several to greater than 10,000-fold decrease in gene expression. In a time-course analysis we found that 2-PE also altered the expression patterns of chromatin modifying genes, MYST1, MYST2, MYST3, gcn5, hdaA and rpdA. The biocontrol capacity of P. anomala can be attributed to the production of 2-PE, which affects spore germination, growth, toxin production, and gene expression in A. flavus.