Division of Environmental Engineering, Faculty of Engineering, Hokkaido University, North-13, West-8, Kita-ku, Sapporo, Hokkaido 060-8628, Japan.
Department of Civil and Environmental Engineering, National Institute of Technology, Kure College, 2-2-11 Agaminami, Kure, Hiroshima 737-8506, Japan.
Syst Appl Microbiol. 2017 Oct;40(7):448-457. doi: 10.1016/j.syapm.2017.07.004. Epub 2017 Aug 18.
We successfully enriched a novel anaerobic ammonium-oxidizing (anammox) bacterium affiliated with the genus 'Candidatus Brocadia' with high purity (>90%) in a membrane bioreactor (MBR). The enriched bacterium was distantly related to the hitherto characterized 'Ca. Brocadia fulgida' and 'Ca. Brocadia sinica' with 96% and 93% of 16S ribosomal RNA gene sequence identity, respectively. The bacterium exhibited the common structural features of anammox bacteria and produced hydrazine in the presence of hydroxylamine under anoxic conditions. The temperature range of anammox activity was 20-45°C with a maximum activity at 37°C. The maximum specific growth rate (μ) was 0.0082h at 37°C, corresponding to a doubling time of 3.5 days. The half-saturation constant (K) for nitrite was 5±2.5μM. The anammox activity was inhibited by nitrite (IC=11.6mM) but not by formate and acetate. The major respiratory quinone was identified to be menaquinone-7 (MK-7). The enriched anammox bacterium shared nearly half of genes with 'Ca. Brocadia sinica' and 'Ca. Brocadia fulgida'. The enriched bacterium showed all known physiological characteristics of anammox bacteria and can be distinguished from the close relatives by its 16S rRNA gene sequence. Therefore, we proposed the name 'Ca. Brocadia sapporoensis' sp. nov.
我们成功地在膜生物反应器（MBR）中以高纯度（>90%）富集了一种新型的厌氧氨氧化（anammox）细菌，隶属于“Candidatus Brocadia”属。该富集菌与迄今为止所描述的“Ca. Brocadia fulgida”和“Ca. Brocadia sinica”具有 96%和 93%的 16S 核糖体 RNA 基因序列同一性，亲缘关系较远。该细菌表现出 anammox 细菌的共同结构特征，并在缺氧条件下在羟胺存在的情况下产生肼。anammox 活性的温度范围为 20-45°C，在 37°C 时最大活性。最大比生长速率（μ）在 37°C 时为 0.0082h，相应的倍增时间为 3.5 天。亚硝酸盐的半饱和常数（K）为 5±2.5μM。亚硝酸根抑制 anammox 活性（IC=11.6mM），但不抑制甲酸盐和乙酸盐。主要呼吸醌被鉴定为甲萘醌-7（MK-7）。富集的 anammox 细菌与“Ca. Brocadia sinica”和“Ca. Brocadia fulgida”共享近一半的基因。富集菌表现出 anammox 细菌的所有已知生理特征，并且可以通过其 16S rRNA 基因序列与近亲区分开来。因此，我们提议将该富集菌命名为“Ca. Brocadia sapporoensis”sp. nov.
