Monitoring bacterial population dynamics using real-time PCR during the bioremediation of crude-oil-contaminated soil.
We evaluated the activity and abundance of the crude oil- degrading bacterium Nocardia sp. H17-1 during bioremediation of oil-contaminated soil, using real-time PCR. The total petroleum hydrocarbon (TPH) degradation rate constants (k) of the soils treated with and without H17-1 were 0.103 d-1 and 0.028 d-1, respectively. The degradation rate constant was 3.6 times higher in the soil with H17-1 than in the soil without H17-1. In order to detect and quantify the Nocardia sp. H17-1 in soil samples, we quantified the genes encoding 16S ribosomal RNA (16S rRNA), alkane monooxygenase (alkB4), and catechol 2,3-dioxygenase (23CAT) with real-time PCR using SYBR green. The amounts of H17-1 16S rRNA and alkB4 detected increased rapidly up to 1,000-folds for the first 10 days, and then continued to increase only slightly or leveled off. However, the abundance of the 23CAT gene detected in H17-1-treated soil, where H17-1 had neither the 23CAT gene for the degradation of aromatic hydrocarbons nor the catechol 2,3-dioxygenase activity, did not differ significantly from that of the untreated soil (alpha=0.05, p>0.22). These results indicated that H17-1 is a potential candidate for the bioaugmentation of alkane-contaminated soil. Overall, we evaluated the abundance and metabolic activity of the bioremediation strain H17-1 using real-time PCR, independent of cultivation.
Environmental Biotechnology Research Center, KRIBB, Daejoen 305-806, Korea.
Kyung-Hwa
KH
Baek
Byung-Dae
BD
Yoon
Dae-Hyun
DH
Cho
Byung-Hyuk
BH
Kim
Hee-Mock
HM
Oh
Hee-Sik
HS
Kim
D000704:Analysis of Variance; D001673:Biodegradation, Environmental; D015169:Colony Count, Microbial; D005798:Genes, Bacterial; D006838:Hydrocarbons / Q000378:metabolism; D007700:Kinetics; D016014:Linear Models; D006899:Mixed Function Oxygenases / Q000235:genetics / Q000378:metabolism; D009615:Nocardia / Q000201:enzymology / Q000235:genetics / Q000254:growth & development* / Q000378:metabolism; D010578:Petroleum / Q000378:metabolism*; D016133:Polymerase Chain Reaction / Q000379:methods*; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D012989:Soil Pollutants / Q000378:metabolism*
D006838:Hydrocarbons; D010578:Petroleum; D012336:RNA, Ribosomal, 16S; D012989:Soil Pollutants; D006899:Mixed Function Oxygenases