Department of Environmental Engineering, Technical University of Denmark, DK-2800 Lyngby, Denmark.
Environ Microbiol. 2010 Oct;12(10):2858-72. doi: 10.1111/j.1462-2920.2010.02267.x.
The link between nitritation success in a membrane-aerated biofilm reactor (MABR) and the composition of the initial ammonia- and nitrite-oxidizing bacterial (AOB and NOB) population was investigated. Four identically operated flat-sheet type MABRs were initiated with two different inocula: from an autotrophic nitrifying bioreactor (Inoculum A) or from a municipal wastewater treatment plant (Inoculum B). Higher nitritation efficiencies (NO(2)(-)-N/NH(4)(+)-N) were obtained in the Inoculum B- (55.2-56.4%) versus the Inoculum A- (20.2-22.1%) initiated reactors. The biofilms had similar oxygen penetration depths (100-150 µm), but the AOB profiles [based on 16S rRNA gene targeted real-time quantitative PCR (qPCR)] revealed different peak densities at or distant from the membrane surface in the Inoculum B- versus A-initiated reactors, respectively. Quantitative fluorescence in situ hybridization (FISH) revealed that the predominant AOB in the Inoculum A- and B-initiated reactors were Nitrosospira spp. (48.9-61.2%) versus halophilic and halotolerant Nitrosomonas spp. (54.8-63.7%), respectively. The latter biofilm displayed a higher specific AOB activity than the former biofilm (1.65 fmol cell(-1) h(-1) versus 0.79 fmol cell(-1) h(-1) ). These observations suggest that the AOB and NOB population compositions of the inoculum may determine dominant AOB in the MABR biofilm, which in turn affects the degree of attainable nitritation in an MABR.
研究了膜曝气生物膜反应器（MABR）中硝化成功与初始氨氧化菌（AOB）和亚硝酸盐氧化菌（NOB）种群组成之间的关系。四个相同操作的平板式 MABR 分别用两种不同的接种物启动：来自自养硝化生物反应器（接种物 A）或来自城市污水处理厂（接种物 B）。接种物 B（55.2-56.4%）启动的反应器比接种物 A（20.2-22.1%）启动的反应器获得更高的亚硝化效率（NO2--N/NH4+-N）。生物膜具有相似的氧渗透深度（100-150 µm），但基于 16S rRNA 基因靶向实时定量 PCR（qPCR）的 AOB 图谱显示，在接种物 B 启动的反应器中，AOB 分别在膜表面附近或远处达到不同的峰值密度，而在接种物 A 启动的反应器中则没有。定量荧光原位杂交（FISH）显示，接种物 A 和 B 启动的反应器中的主要 AOB 分别为 Nitrosospira spp.（48.9-61.2%）和嗜盐和耐盐的 Nitrosomonas spp.（54.8-63.7%）。后一种生物膜的 AOB 比前一种生物膜具有更高的比活性（1.65 fmol 细胞-1 h-1 比 0.79 fmol 细胞-1 h-1 ）。这些观察结果表明，接种物中的 AOB 和 NOB 种群组成可能决定了 MABR 生物膜中的优势 AOB，进而影响 MABR 中可达到的亚硝化程度。
