铜离子抑制作用下的硝化菌群amoA mRNA动态特征

Character of amoA mRNA During Nitrifying Inhibition by Cu2+

摘要:

研究考察了不同质量浓度Cu2+离子(10,20,50 mg·L-1)对活性污泥硝化菌群活性的抑制作用,采用RNA反转录结合RealTime PCR（实时聚合酶链式反应）定量测定技术,分析了受到金属离子抑制后,硝化菌群在短期内(10 h)氨单加氧酶编码信息核糖核酸 (ammonia monooxygenase encoding messenger ribonucleic acid,amoA mRNA)的受抑变化特征,结果表明Cu2+可以显著抑制活性污泥硝化菌群的amoA mRNA水平,且抑制程度随金属离子浓度的升高而增强.amoA mRNA显著抑制出现的时间要先于硝化速率抑制.抑制作用在从amoA mRNA传导至代谢活性存在一定的滞后时间,根据实验结果推断amoA mRNA合成受抑可能是Cu2+生物硝化抑制的分子途径之一.

Abstract:

The profile of ammonia monooxygenase encoding messenger ribonucleic acid (amoA mRNA) was examined due to inhibition by Cu2+ (10,20,50 mg·L-1) during a short reaction period(10hour).The test was performed by several continuously fed nitrification reactors and the realtime reverse transcriptionPCR method was applied to detect change character of amoA mRNA.The Cu2+could affect amoA mRNA copies in activated sludge,and higher concentration of Cu2+would lead to more inhibition for amoA mRNA level.The decrease of amoA mRNA was more early observed before decrease of nitrifying rate.After mRNA inhibition happened,a lagging time prior to notable decrease in nitrifying rate was detected.So the nitrification inhibition was likely performed thought impact on transcription of amoA mRNA by Cu2+.