Monitoring 4-Chlorobiphenyl-Degrading Bacteria in Soil Microcosms by Competitive Quantitative PCR

다국어 초록 (Multilingual Abstract)

The competitive quantitative PCR method targeting pcbC gene was developed for monitoring 4-chlorobiphenyl(
4CB)-degrading bacteria, Pseudomonas sp. strain DJ-12, in soil microcosms. The method
involves extraction of DNA from soil contaminated with 4CB, PCR amplification of a pcbC gene fragment
from the introduced strain with a set of strain-specific primers, and quantification of the electrophoresed
PCR product by densitometry. To test the adequacy of the method, Pseudomonas sp. strain
DJ-12 was introduced into both contaminated and non-contaminated soil microcosms amended with
4CB. Pseudomonas sp. strain DJ-12 was monitored and quantified by a competitive quantitative PCR
in comparison with 4CB degradation and the result was compared to those obtained by using the conventional
cultivation method. We successfully detected and monitored 4CB-degrading bacteria in each
microcosm and found a significant linear relationship between the number of 4CB-degrading bacteria
and the capacity for 4CB biodegradation. The results of DNA spiking and cell-spreading experiments
suggest that this competitive quantitative PCR method targeting the pcbC gene for monitoring 4CBdegrading
bacteria appears to be rapid, sensitive and more suitable than the microbiological approach
in estimating the capacity of 4CB biodegradation in environmental samples.

다국어 초록 (Multilingual Abstract)

4CB)-degrading bacteria, Pseudomonas sp. strain DJ-12, in soil microcosms. The methodinvolves extraction of DNA from soil contaminated with 4CB, PCR amplification of a pcbC gene fragmentfrom the introduced strain with a set of strain-specific primers, and quantification of the electrophoresedPCR product by densitometry. To test the adequacy of the method, Pseudomonas sp. strainDJ-12 was introduced into both contaminated and non-contaminated soil microcosms amended with4CB. Pseudomonas sp. strain DJ-12 was monitored and quantified by a competitive quantitative PCRin comparison with 4CB degradation and the result was compared to those obtained by using the conventionalcultivation method. We successfully detected and monitored 4CB-degrading bacteria in eachmicrocosm and found a significant linear relationship between the number of 4CB-degrading bacteriaand the capacity for 4CB biodegradation. The results of DNA spiking and cell-spreading experimentssuggest that this competitive quantitative PCR method targeting the pcbC gene for monitoring 4CBdegradingbacteria appears to be rapid, sensitive and more suitable than the microbiological approachin estimating the capacity of 4CB biodegradation in environmental samples.