Department of Microbiology, IWWR, Radboud University, Nijmegen, the Netherlands.
Soehngen Institute of Anaerobic Microbiology, Nijmegen, the Netherlands.
Appl Environ Microbiol. 2019 Apr 4;85(8). doi: 10.1128/AEM.00124-19. Print 2019 Apr 15.
Nitrite-dependent methane-oxidizing bacteria couple the reduction of nitrite to the oxidation of methane via a unique oxygen-producing pathway. This process is carried out by members of the genus that belong to the NC10 phylum. Contrary to other known anaerobic methane oxidizers, they do not employ the reverse methanogenesis pathway for methane activation but instead a canonical particulate methane monooxygenase similar to those used by aerobic methanotrophs. -like bacteria are detected in many natural and manmade ecosystems, but their physiology is not well understood. Here, using continuous cultivation techniques, batch activity assays, and state-of-the-art membrane-inlet mass spectrometry, we determined growth rate, doubling time, and methane and nitrite affinities of the nitrite-dependent methane-oxidizing bacterium " Methylomirabilis lanthanidiphila." Our results provide insight into understanding the interactions of these microorganisms with methanotrophs and other nitrite-reducing microorganisms, such as anaerobic ammonium-oxidizing bacteria. Furthermore, our data can be used in modeling studies as well as wastewater treatment plant design. Methane is an important greenhouse gas with a radiative forcing 28 times that of carbon dioxide over a 100-year time scale. The emission of methane to the atmosphere is controlled by aerobic and anaerobic methanotrophs, which are microorganisms that are able to oxidize methane to conserve energy. While aerobic methanotrophs have been studied for over a century, knowledge on the physiological characteristics of anaerobic methanotrophs is scarce. Here, we describe kinetic properties of " Methylomirabilis lanthanidiphila," a nitrite-dependent methane-oxidizing microorganism, which is ecologically important and can be applied in wastewater treatment.
亚硝酸盐依赖型甲烷氧化菌通过一种独特的产氧途径将亚硝酸盐的还原与甲烷的氧化偶联起来。这一过程是由属于 NC10 门的 属的成员完成的。与其他已知的厌氧甲烷氧化菌不同，它们不采用逆甲烷生成途径来激活甲烷，而是采用类似于好氧甲烷营养菌所使用的典型颗粒态甲烷单加氧酶。在许多自然和人为生态系统中都检测到了 样细菌，但它们的生理学特性还不是很清楚。在这里，我们使用连续培养技术、批量活性测定和最先进的膜进样质谱，确定了亚硝酸盐依赖型甲烷氧化菌“Methylomirabilis lanthanidiphila”的生长速率、倍增时间以及甲烷和亚硝酸盐亲和力。我们的研究结果为理解这些微生物与甲烷营养菌和其他亚硝酸盐还原微生物（如厌氧氨氧化菌）的相互作用提供了依据。此外，我们的数据可以用于模型研究和废水处理厂的设计。甲烷是一种重要的温室气体，其在 100 年时间尺度上的辐射强迫是二氧化碳的 28 倍。甲烷向大气中的排放受好氧和厌氧甲烷营养菌的控制，这些微生物能够将甲烷氧化以保存能量。虽然好氧甲烷营养菌已经研究了一个多世纪，但对厌氧甲烷营养菌的生理特性知之甚少。在这里，我们描述了一种亚硝酸盐依赖型甲烷氧化微生物“Methylomirabilis lanthanidiphila”的动力学特性，该微生物在生态学上很重要，并可应用于废水处理。
