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16S Ribosomal RNA Tools Identify an Unexpected Predominance of Paenibacillus-Like Bacteria in an Industrial Activated Sludge System Suffering from Poor Biosolids Separation
Water Environment Research
  • Joyce M. Simpson
  • Peter George Stroot
  • Steve Gelman
  • Inan Beydilli
  • Sandra Dudley
  • Daniel B. Oerther, Missouri University of Science and Technology
Molecular biology tools targeting 16S ribosomal RNA (16S rRNA) were used to identify a predominant bacterial population in a full-scale dairy wastewater activated sludge system suffering from poor biosolids separation. Gram and acridine orange staining indicated that viable, Gram-positive microorganisms were present in samples removed from the influent waste, stream and represented approximately 50% of total cell counts in samples removed from the mixed liquor. Subsequently, the "full-cycle 16S rRNA approach" showed that phylogenetic relatives of Paenibacillus spp., a low guanine-plus-cytosine percent DNA-content, Gram-positive microorganism, represented up to 30% of total 4,6-diamidino-2-phenylindole (DAPI)-stained cell counts in samples of mixed liquor. Although fluorescent in situ hybridizations with 16S rRNA-targeted oligonucleotide hybridization probes identified Paenibacillus-like spp. in samples removed from the influent waste stream, their abundance was less than 10% of total stained cell counts. Results of this study suggest that Paenibacillus-like spp. were present in low abundance in the influent waste stream, increased in relative abundance within the treatment system, and should be examined further as a candidate bacterial population responsible for poor biosolids separation. This study demonstrates that the full-cycle 16S rRNA approach can be used to identify candidate bacterial populations that may be responsible for operational upsets in full-scale activated sludge systems without prior information from cultivation or microscopic analyses.
Civil, Architectural and Environmental Engineering
Keywords and Phrases
  • 16S ribosomal RNA,
  • Activated sludge,
  • Dairy food processing,
  • Paenibacillus spp.,
  • Bacteria,
  • Dyes,
  • Molecular biology,
  • RNA,
  • Wastewater,
  • Wastewater treatment,
  • Activated sludge process,
  • 4',6 diamidino 2 phenylindole,
  • acridine orange,
  • oligonucleotide,
  • RNA 16S,
  • abundance,
  • bacterium,
  • biosolid,
  • phylogenetics,
  • water treatment,
  • bacterium identification,
  • cell count,
  • dairying,
  • fluorescence in situ hybridization,
  • Gram staining,
  • nonhuman,
  • oligonucleotide probe,
  • Paenibacillus,
  • phylogeny,
  • priority journal,
  • RNA analysis,
  • waste water management,
  • Bacillaceae,
  • Dairy Products,
  • Equipment Failure,
  • Food Industry,
  • Industrial Waste,
  • Models,
  • Biological,
  • Bacterial,
  • Ribosomal,
  • 16S,
  • Ultrafiltration,
  • Waste Disposal,
  • Fluid,
  • Water Microbiology,
  • Bacteria (microorganisms),
  • Posibacteria
Document Type
Article - Journal
Document Version
File Type
© 2006 Water Environment Federation, All rights reserved.
Publication Date
Citation Information
Joyce M. Simpson, Peter George Stroot, Steve Gelman, Inan Beydilli, et al.. "16S Ribosomal RNA Tools Identify an Unexpected Predominance of Paenibacillus-Like Bacteria in an Industrial Activated Sludge System Suffering from Poor Biosolids Separation" Water Environment Research Vol. 78 Iss. 8 (2006) p. 864 - 871 ISSN: 10614303
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