qPCR quantification and genetic characterization of Clostridium perfringens populations in biosolids composted for 2 years.
OBJECTIVE
The ability of Clostridium perfringens to survive for a long time in the environment makes it a suitable indicator of faecal pollution, but its use as a routine indicator organism in biosolids and composted biosolids has not yet been adopted. This study was performed to improve our understanding of C. perfringens persistence in composted biosolids by monitoring its presence and studying its genetic diversity.


RESULTS
A culture-independent TaqMan qPCR assay targeting the cpn60 gene was adapted to enumerate C. perfringens in composted biosolid samples varying in age from 1 to 24 months. The pathogen was detected in all compost samples under study, but no correlation between composting time and number of cpn60 copies was observed. Rep-PCR detected 14 different C. perfringens genotypes, all belonging to toxinotype A, which is the most common biotype found in human and animal gastrointestinal tracts.


CONCLUSIONS
Composting did not significantly decrease the number of C. perfringens cells. High genetic diversity of C. perfringens isolates present in composted biosolids is reported for the first time.


CONCLUSIONS
This study evaluated tools for surveillance of composting processes, source tracking and risk assessment of composted biosolids.
Karpowicz
E
E
Department of Biology, Mount Allison University, Sackville, NB, Canada.
Novinscak
A
A
Bärlocher
F
F
Filion
M
M
D003016:Clostridium perfringens / Q000235:genetics* / Q000302:isolation & purification*; D016000:Cluster Analysis; D004269:DNA, Bacterial / Q000302:isolation & purification; D005798:Genes, Bacterial; D014644:Genetic Variation; D005838:Genotype; D010802:Phylogeny; D016133:Polymerase Chain Reaction / Q000379:methods; D012037:Refuse Disposal; D017422:Sequence Analysis, DNA; D012722:Sewage / Q000382:microbiology*; D012987:Soil / Q000032:analysis; D012988:Soil Microbiology; D013997:Time Factors
D004269:DNA, Bacterial; D012722:Sewage; D012987:Soil