Ullrich Sophie R, Poehlein Anja, Levicán Gloria, Mühling Martin, Schlömann Michael
Institut für Biowissenschaften, Technische Universität Bergakademie Freiberg, Leipziger Straße 29, 09599, Freiberg, Germany.
Göttingen Genomics Laboratory, Georg-August-Universität Göttingen, Grisebachstraße 8, 37073, Göttingen, Germany.
Res Microbiol. 2018 Dec;169(10):618-627. doi: 10.1016/j.resmic.2018.05.009. Epub 2018 Jun 2.
The response of the acidophilic iron oxidizer "Ferrovum" sp. JA12 to elevated concentrations of ferrous iron was targeted at transcriptome level in order to assess models on oxidative stress management and ferrous iron oxidation. Overall transcriptome profiles indicate a high cellular activity of "Ferrovum" sp. JA12 up to 50 mM of ferrous iron with genes predicted to be involved in iron oxidation, carbon fixation and ribosome formation showing the highest transcript levels. The data support the iron oxidation pathway inferred from genome analysis and draws attention to further redox proteins potentially associated with iron oxidation. The restriction of homologous proteins to iron oxidizing beta- and zetaproteobacteria underlines the previous notion of a common origin of iron oxidation in these phyla. Detoxification of reactive oxygen species and primary products of oxidative damage of membrane lipids appears to be of permanent relevance under conditions mimicking those of the original habitat of "Ferrovum" sp. JA12. Also the maintenance of a reverse membrane potential appears to be its most important strategy to withstand the acidic external pH.
嗜酸铁氧化菌“Ferrovum” sp. JA12对亚铁离子浓度升高的响应在转录组水平上进行了研究，以评估氧化应激管理和亚铁离子氧化的模型。整体转录组图谱表明，在高达50 mM的亚铁离子环境中，“Ferrovum” sp. JA12具有较高的细胞活性，预测参与铁氧化、碳固定和核糖体形成的基因转录水平最高。这些数据支持了从基因组分析推断出的铁氧化途径，并关注到可能与铁氧化相关的其他氧化还原蛋白。同源蛋白局限于铁氧化β-变形菌和ζ-变形菌，这突出了之前关于这些门类中铁氧化具有共同起源的观点。在模拟“Ferrovum” sp. JA12原始栖息地的条件下，活性氧的解毒和膜脂氧化损伤的初级产物似乎一直具有重要意义。维持反向膜电位似乎也是其抵御外部酸性pH值的最重要策略。
