Application of quantitative RT-PCR to determine the distribution of Microthrix parvicella in full-scale activated sludge treatment systems.
Three wastewater treatment plants in South Africa were investigated to understand the phylogeny and distribution of Microthrix parvicella using real-time polymerase chain reaction (RT-PCR). The phylogenetic analysis of the 16S rRNA of M. parvicella revealed 98% to 100% homology of South African clones to M. parvicella reported in Genbank. The standard curves for RT-PCR showed R2 values greater than 0.99, accurate for quantification. The relative occurrence of M. parvicella 16S rRNA gene copies in the three wastewater treatment plants was in the range 0% to 3.97%. M. parvicella copies increased when the environmental temperature (< or =20 degrees C) and food/microorganism (F/M) ratio was low. The M. parvicella 16S rRNA copies could be positively correlated to the sludge volume index at low temperature. At higher temperature, there was a rapid reduction in M. parvicella population irrespective of other favorable factors, indicating the strong influence of temperature on filamentous proliferation. RT-PCR has potential applications in wastewater treatment plants to monitor sudden shift in the microbial population and assessing the plants efficacy.
Kumari
S K Sheena
SK
Department of Biotechnology and Food Technology, Durban University of Technology, South Africa. sheenas@dut.ac.za
Marrengane
Z
Z
Bux
F
F
D039903:Actinobacteria / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification*; D016000:Cluster Analysis; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D004275:DNA, Ribosomal / Q000737:chemistry / Q000235:genetics; D008969:Molecular Sequence Data; D010802:Phylogeny; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000379:methods*; D017422:Sequence Analysis, DNA; D012722:Sewage / Q000382:microbiology*; D013019:South Africa; D013696:Temperature
D004269:DNA, Bacterial; D004275:DNA, Ribosomal; D012336:RNA, Ribosomal, 16S; D012722:Sewage