Gülay Arda, Çekiç Yağmur, Musovic Sanin, Albrechtsen Hans-Jørgen, Smets Barth F
Department of Environmental Engineering, Technical University of Denmark, Kongens Lyngby, Denmark.
Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA, United States.
Front Microbiol. 2018 Dec 3;9:2808. doi: 10.3389/fmicb.2018.02808. eCollection 2018.
Although earlier circumstantial observations have suggested the presence of iron oxidizing bacteria (IOB) in groundwater-fed rapid sand filters (RSF), ferrous iron (Fe(II)) oxidation in this environment is often considered a chemical process due to the highly oxic and circumneutral pH conditions. The low water temperature (5-10°C), typical of groundwaters, on the other hand, may reduce the rates of chemical Fe(II) oxidation, which may allow IOB to grow and compete with chemical Fe(II) oxidation. Hence, we hypothesized that IOB are active and abundant in groundwater-fed RSFs. Here, we applied a combination of cultivation and molecular approaches to isolate, quantify, and confirm the growth of IOB from groundwater-fed RSFs, operated at different influent Fe(II) concentrations. Isolates related to and were identified as novel IOB lineages. spp. were dominant in all waterworks, whereas and were dominant at pre-filters of waterworks receiving groundwaters with high (>2 mg/l) Fe(II) concentrations. The high density and diversity of IOB in groundwater-fed RSFs suggest that neutrophilic IOB may not be limited to oxic/anoxic interfaces.
尽管早期的间接观察表明，在以地下水为水源的快速砂滤池（RSF）中存在铁氧化细菌（IOB），但由于该环境中氧含量高且pH值接近中性，亚铁（Fe(II)）氧化通常被认为是一个化学过程。另一方面，典型的地下水低温（5-10°C）可能会降低化学Fe(II)氧化速率，这可能会使IOB生长并与化学Fe(II)氧化竞争。因此，我们推测IOB在以地下水为水源的RSF中具有活性且数量丰富。在此，我们应用培养和分子方法相结合的手段，从不同进水Fe(II)浓度运行的以地下水为水源的RSF中分离、定量并确认IOB的生长。与 和 相关的分离株被鉴定为新的IOB谱系。 spp. 在所有水厂中占主导地位，而 在接收高Fe(II)浓度（>2 mg/l）地下水的水厂的预滤池中占主导地位。以地下水为水源的RSF中IOB的高密度和多样性表明，嗜中性IOB可能不限于有氧/缺氧界面。
