A gene from Aspergillus nidulans with similarity to URE2 of Saccharomyces cerevisiae encodes a glutathione S-transferase which contributes to heavy metal and xenobiotic resistance
A gene from Aspergillus nidulans with similarity to URE2 of Saccharomyces cerevisiae encodes a glutathione S-transferase which contributes to heavy metal and xenobiotic resistance
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DOI：
10.1128/aem.68.6.2802-2808.2002
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发表时间：
2002-06-01
影响因子：
4.4
通讯作者：
Hynes, MJ
中科院分区：
文献类型：
--
作者：
Fraser, JA;Davis, MA;Hynes, MJ
构巢曲霉是一种利用多种氮源的腐殖型子囊菌。我们鉴定了A的一个序列。类似于酿酒酵母Ure 2的谷胱甘肽S-转移酶样氮调节结构域的nidulans。对该基因（命名为gstA）的克隆和测序显示，它与URE 2比S.酿酒酵母谷胱甘肽S-转移酶。然而，gstA缺失突变体的创建和分析显示，该基因不参与氮代谢物阻遏。相反，它编码一种功能性θ类谷胱甘肽S-转移酶，该酶参与对多种外源性物质和金属的抗性，并赋予对内吸性杀真菌剂羧菌素的敏感性。北方分析表明，gstA转录强烈激活后，暴露于1-氯-2，4-二硝基苯和弱激活的氧化应激或生长上的半乳糖作为碳源。这些结果表明，氮代谢阻遏在A。nidulans不涉及S.酿酒酵母URE 2基因，并在这两种真菌的全球氮调节系统显着不同。
Aspergillus nidulans is a saprophytic ascomycete that utilizes a wide variety of nitrogen sources. We identified a sequence from A. nidulans similar to the glutathione S-transferase-like nitrogen regulatory domain of Saccharomyces cerevisiae Ure2. Cloning and sequencing of the gene, designated gstA, revealed it to be more similar to URE2 than the S. cerevisiae glutathione S-transferases. However, creation and analysis of a gstA deletion mutant revealed that the gene does not participate in nitrogen metabolite repression. Instead, it encodes a functional theta class glutathione S-transferase that is involved in resistance to a variety of xenobiotics and metals and confers susceptibility to the systemic fungicide carboxin. Northern analysis showed that gstA transcription is strongly activated upon exposure to 1-chloro-2,4-dinitrobenzene and weakly activated by oxidative stress or growth on galactose as a carbon source. These results suggest that nitrogen metabolite repression in A. nidulans does not involve a homolog of the S. cerevisiae URE2 gene and that the global nitrogen regulatory system differs significantly in these two fungi.