Bakti Fruzsina, Sasse Christoph, Heinekamp Thorsten, Pócsi István, Braus Gerhard H
Institute for Microbiology and Genetics, Department of Molecular Microbiology and Genetics, Goettingen Center for Molecular Biosciences, University of Göttingen, Göttingen, Germany.
Department of Biotechnology and Microbiology, Faculty of Science and Technology, University of Debrecen, Debrecen, Hungary.
Front Microbiol. 2018 Apr 13;9:744. doi: 10.3389/fmicb.2018.00744. eCollection 2018.
Most of the metal transporters in are yet uncharacterized. Their role in fungal metabolism and virulence remains unclear. This paper describes the novel PIB-type cation ATPase PcaA, which links metal homeostasis and heavy metal tolerance in the opportunistic human pathogen . The protein possesses conserved ATPase motif and shares 51% amino acid sequence identity with the cadmium exporter Pca1p. A deletion, an overexpression and a complementation strain of were constructed and their heavy metal susceptibilities were studied. The knock out strain showed drastically decreased cadmium tolerance, however, its growth was not affected by the exposure to high concentrations of copper, iron, zinc, or silver ions. Although the lack of PcaA had no effect on copper adaption, we demonstrated that not only cadmium but also copper ions are able to induce the transcription of in wild type Af293. Similarly, cadmium and copper ions could induce the copper exporting ATPase . These data imply a general response on the transcriptomic level to heavy metals in through the induction of detoxification systems. Confocal microscopy of the complementation strain expressing functional GFP-PcaA supports the predicted membrane localization of PcaA. The GFP-PcaA fusion protein is located in the plasma membrane of in the presence of cadmium ions. Virulence assays support a function of PcaA for virulence of in the wax moth larvae model, which might be linked to the elimination of reactive oxygen species.
大多数[具体真菌名称未给出]中的金属转运蛋白尚未得到表征。它们在真菌代谢和毒力中的作用仍不清楚。本文描述了新型PIB型阳离子ATP酶PcaA，它在机会性人类病原体[具体真菌名称未给出]中连接金属稳态和重金属耐受性。该蛋白具有保守的ATP酶基序，与[具体真菌名称未给出]的镉输出蛋白Pca1p具有51%的氨基酸序列同一性。构建了[具体真菌名称未给出]的缺失、过表达和互补菌株，并研究了它们对重金属的敏感性。[具体真菌名称未给出]敲除菌株显示出镉耐受性大幅下降，然而，其生长不受高浓度铜、铁、锌或银离子暴露的影响。虽然缺乏PcaA对铜适应性没有影响，但我们证明不仅镉离子而且铜离子都能够在野生型Af293中诱导[具体真菌名称未给出]的转录。同样，镉离子和铜离子可以诱导铜输出ATP酶。这些数据表明[具体真菌名称未给出]在转录组水平上通过诱导解毒系统对重金属有普遍反应。表达功能性GFP - PcaA的[具体真菌名称未给出]互补菌株的共聚焦显微镜观察支持了PcaA预测的膜定位。在镉离子存在下，GFP - PcaA融合蛋白位于[具体真菌名称未给出]的质膜中。毒力测定支持PcaA在大蜡螟幼虫模型中对[具体真菌名称未给出]毒力的作用，这可能与活性氧的消除有关。
