Leachates from municipal solid waste disposal sites harbor similar, novel nitrogen-cycling bacterial communities

Shuang Zhu, Yuk Sing Gilbert Chan, Kai Long Cai, Liang Hu Qu, Li Nan Huang

Research output: Journal article publicationJournal articleAcademic researchpeer-review

14 Citations (Scopus)


High emissions of nitrous oxide (N2O) have recently been documented at municipal solid waste (MSW) landfills. However, the biodiversity of the bacterial populations involved remains unexplored. In this study, we investigated communities of ammonia-oxidizing bacteria (AOB) and denitrifying bacteria associated with the leachates from three MSW disposal sites by examining the diversity of the ammonia monooxygenase structural gene amoA and the nitrous oxide reductase gene nosZ, respectively. Cloning and phylogenetic analysis of the functional genes revealed novel and similar groups of prokaryotes involved in nitrogen cycling in the leachates with different chemical compositions. All amoA sequences recovered grouped within the Nitrosomonas europaea cluster in the Betaproteobacteria, with the vast majority showed only relatively moderate sequence similarities to known AOB but were exclusively most similar to environmental clones previously retrieved from wastewater treatment plants. All nosZ sequences retrieved did not cluster with any hitherto reported nosZ genes and were only remotely related to recognized denitrifiers from the Gammaproteobacteria and thus could not be affiliated. Significant overlap was found for the three denitrifying nosZ leachate communities. Our study suggests a significant selection of the novel N-cycling groups by the unique environment at these MSW disposal sites.
Original languageEnglish
Pages (from-to)236-242
Number of pages7
JournalFEMS Microbiology Letters
Issue number2
Publication statusPublished - 1 Feb 2007


  • Ammonia-oxidizing bacteria
  • amoA
  • Denitrifying bacteria
  • Municipal solid waste
  • Nitrous oxide
  • nosZ

ASJC Scopus subject areas

  • Microbiology
  • Molecular Biology
  • Genetics

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