Analysis of the bacterial community inhabiting an aerobic thermophilic sequencing batch reactor (AT-SBR) treating swine waste.
The microflora of a self-heating aerobic thermophilic sequencing batch reactor (AT-SBR) treating swine waste was investigated by a combination of culture and culture-independent techniques. The temperature increased quickly in the first hours of the treatment cycles and values up to 72 degrees C were reached. Denaturing gradient gel electrophoresis of the PCR-amplified V3 region of 16S rDNA (PCR-DGGE) revealed important changes in the bacterial community during 3-day cycles. A clone library was constructed with the near-full-length 16S rDNA amplified from a mixed-liquor sample taken at 60 degrees C. Among the 78 non-chimeric clones analysed, 20 species (here defined as clones showing more than 97% sequence homology) were found. In contrast to other culture-independent bacterial analyses of aerobic thermophilic wastewater treatments, species belonging to the Bacilli class were dominant (64%) with Bacillus thermocloacae being the most abundant species (38%). The other Bacilli could not be assigned to a known species. Schineria larvae was the second most abundant species (14%) in the clone library. Four species were also found among the 19 strains isolated, cultivated and identified from samples taken at 40 degrees C and 60 degrees C. Ten isolates showed high 16S rDNA sequence homology with the dominant bacterium of a composting process that had not been previously isolated.
Juteau
P
P
INRS-Institut Armand-Frappier, Université du Québec, 531 Boulevard des Prairies, Laval, QC H7V 1B7, Canada. pierre.juteau@inrs-iaf.uquebec.ca
Tremblay
D
D
Villemur
R
R
Bisaillon
J-G
JG
Beaudet
R
R
D000818:Animals; D001419:Bacteria / Q000145:classification*; D019149:Bioreactors / Q000382:microbiology* / Q000662:veterinary; D004269:DNA, Bacterial / Q000032:analysis; D005243:Feces / Q000382:microbiology; D015723:Gene Library; D012722:Sewage; D013552:Swine / Q000382:microbiology
D004269:DNA, Bacterial; D012722:Sewage