Third K A, Paxman J, Schmid M, Strous M, Jetten M S M, Cord-Ruwisch R
Biotechnology Department, Division of Science and Engineering, Murdoch University, South Street, Murdoch, WA 6150, Australia.
Microb Ecol. 2005 Feb;49(2):236-44. doi: 10.1007/s00248-004-0186-4. Epub 2005 Feb 24.
A microbial culture capable of actively oxidizing ammonium to dinitrogen gas in the absence of oxygen, using nitrite as the electron acceptor, was enriched from local activated sludge (Western Australia) in <14 weeks. The maximum anaerobic ammonium oxidation (i.e., anammox) activity achieved by the anaerobic culture was 0.26 mmol NH (4) (+) (g biomass)(-1) h(-1) (0.58 kg total-N m(-3) day(-1)). Qualitative FISH analysis (fluorescence in situ hybridization) confirmed the phylogenetic position of the enriched microorganism as belonging to the order Planctomycetales, in which all currently identified anammox strains fall. Preliminary FISH analysis suggests the anammox strain belongs to the same phylogenetic group as the Candidatus 'Brocadia anammoxidans' strain discovered in the Netherlands. However, there are quite a few differences in the target sites for the more specific probes of these organisms and it is therefore likely to represent a new species of anammox bacteria. A small amount of aerobic ammonium-oxidizing biomass was inoculated into the anammox reactor (10% v/v) to initiate completely autotrophic nitrogen removal over nitrite (the CANON process) in chemostat culture. The culture was always under oxygen limitation and no organic carbon was added. The CANON reactor was operated as an intermittently aerated system with 20 min aerobiosis and 30 min anaerobiosis, during which aerobic and anaerobic ammonium oxidation were performed in sequential fashion, respectively. Anammox was not inhibited by repeated intermittent exposure to oxygen, allowing sustained, completely autotrophic ammonium removal (0.08 kg N m(-3) day(-1)) for an extended period of time.
在无氧条件下，利用亚硝酸盐作为电子受体，能够将铵态氮主动氧化为氮气的微生物培养物，在不到14周的时间里从西澳大利亚当地的活性污泥中富集得到。该厌氧培养物实现的最大厌氧氨氧化（即anammox）活性为0.26 mmol NH₄⁺（g生物量）⁻¹ h⁻¹（0.58 kg总氮 m⁻³ 天⁻¹）。定性FISH分析（荧光原位杂交）证实了富集微生物的系统发育位置属于浮霉菌目，目前所有已鉴定的anammox菌株都属于该目。初步FISH分析表明，该anammox菌株与在荷兰发现的“Candidatus 'Brocadia anammoxidans'”菌株属于同一系统发育组。然而，这些微生物更特异性探针的靶位点存在相当多差异，因此它很可能代表anammox细菌的一个新物种。将少量好氧氨氧化生物量接种到anammox反应器中（10% v/v），以启动在恒化器培养中通过亚硝酸盐进行的完全自养脱氮（CANON工艺）。培养物始终处于氧气限制条件下，且不添加有机碳。CANON反应器作为间歇曝气系统运行，曝气20分钟，厌氧30分钟，在此期间分别依次进行好氧和厌氧氨氧化。重复间歇暴露于氧气不会抑制anammox，从而能够长时间持续进行完全自养氨去除（0.08 kg N m⁻³ 天⁻¹）。
