Ammonia-oxidizing archaea (AOA) are widespread in nature and are involved in nitrification, an essential process in the global nitrogen cycle. The enzymes for ammonia oxidation and electron transport rely heavily on copper (Cu), which can be limited in nature. In this study the model soil archaeon Nitrososphaera viennensis was investigated via transcriptomic analysis to gain insight regarding possible Cu uptake mechanisms and compensation strategies when Cu becomes limiting. Upon Cu limitation, N. viennensis exhibited impaired nitrite production and thus growth, which was paralleled by downregulation of ammonia oxidation, electron transport, carbon fixation, nucleotide, and lipid biosynthesis pathway genes. Under Cu-limitation, 1547 out of 3180 detected genes were differentially expressed, with 784 genes upregulated and 763 downregulated. The most highly upregulated genes encoded proteins with a possible role in Cu binding and uptake, such as the Cu chelator and transporter CopC/D, disulfide bond oxidoreductase D (dsbD), and multicopper oxidases. While this response differs from the marine strain Nitrosopumilus maritimus, conserved sequence motifs in some of the Cu-responsive genes suggest conserved transcriptional regulation in terrestrial AOA. This study provides possible gene regulation and energy conservation mechanisms linked to Cu bioavailability and presents the first model for Cu uptake by a soil AOA.

氨氧化古细菌（AOA）自然界很普遍，并且参与硝化作用，而硝化作用是全球氮循环的重要过程。用于氨氧化和电子传输的酶在很大程度上依赖于铜（Cu），而铜在自然界中可能受到限制。在这项研究中，通过转录组分析研究了土壤土壤古细菌Nitrososphaera viennensis的模型，以了解有关当Cu变得有限时可能的Cu吸收机制和补偿策略的见解。在铜限制下，维也纳猪笼草表现出亚硝酸盐生成受损，因而生长受损，这与氨氧化，电子转运，碳固定，核苷酸和脂质生物合成途径基因的下调相平行。在铜限制下，检测到的3180个基因中有1547个差异表达，其中784个基因被上调，而763个基因被下调。上调程度最高的基因编码的蛋白质可能与铜的结合和吸收有关，例如铜螯合剂和转运蛋白CopC / D，二硫键氧化还原酶D（dsbD）和多铜氧化酶。虽然这种反应不同于海洋菌株Nitrosopumilus maritimus，一些铜响应基因中的保守序列基序提示了陆地AOA中的保守转录调控。这项研究提供了可能的基因调控和与铜生物利用度相关的节能机制，并提出了土壤AOA吸收铜的第一个模型。