Quantitative analysis of amoA mRNA expression as a new biomarker of ammonia oxidation activities in a complex microbial community

Yoshiteru Aoi, Y. Masaki, S. Tsuneda, A. Hirata

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26 Citations (Scopus)


Aims: To quantitatively analyse the changes to amoA mRNA (ammonia mono-oxygenase encoding mRNA) profiles in response to a change in ammonia oxidation activity in a complex microbial community. Methods and Results: The amoA mRNA levels in both a batch-mode incubation and a continuously fed nitrification reactor were determined by real-time reverse transcription-PCR analysis. The amoA mRNA level changed rapidly in response to the change in environmental conditions which affect ammonia oxidation activity. Conclusion: An increase in amoA mRNA level can be detected within 1-2 h in response to an initiation of cell activity whereas a decrease in amoA mRNA level is detected within 24 h in response to a cessation of activity. Significance and Impact of the Study: amoA mRNA, which shows sensitive response to ammonia oxidation activity, can be used as a biomarker of ammonia oxidation activity in wastewater treatment processes where many bacterial species exist.

Original languageEnglish
Pages (from-to)477-482
Number of pages6
JournalLetters in Applied Microbiology
Issue number6
Publication statusPublished - 2004 Dec 13



  • Ammonia oxidizing bacteria
  • Nitrification
  • Real-time reverse transcription-PCR
  • Wastewater treatment process
  • mRNA
  • rRNA

ASJC Scopus subject areas

  • Applied Microbiology and Biotechnology

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