title: Using real-time PCR to assess changes in the hydrocarbon-degrading microbial community in Antarctic soil during bioremediation.
abstract: A real-time polymerase chain reaction (PCR) method to quantify the proportion of microorganisms containing alkane monooxygenase was developed and used to follow changes in the microbial community in hydrocarbon-contaminated Antarctic soil during a bioremediation field trial. Assays for the alkB and rpoB genes were validated and found to be both sensitive and reproducible (less than 2% intrarun variation and 25-38% interrun variation). Results from the real-time PCR analysis were compared to analysis of the microbial population by a culture-based technique [most probable number (MPN) counts]. Both types of analysis indicated that fertilizer addition to hydrocarbon-contaminated soil stimulated the indigenous bacterial population within 1 year. The proportion of alkB containing microorganisms was positively correlated to the concentration of n-alkanes in the soil. After the concentration of n-alkanes in the soil decreased, the proportion of alkane-degrading microorganisms decreased, but the proportion of total hydrocarbon-degrading microorganisms increased, indicating another shift in the microbial community structure and ongoing biodegradation.
authors.affiliation: Tasmanian Institute of Agricultural Research, University of Tasmania, Hobart 7001, Australia. shane.powell@aad.gov.au
authors.forename: Shane M
authors.initials: SM
authors.lastname: Powell
authors.forename: Susan H
authors.initials: SH
authors.lastname: Ferguson
authors.forename: John P
authors.initials: JP
authors.lastname: Bowman
authors.forename: Ian
authors.initials: I
authors.lastname: Snape
mesh_terms: D000864:Antarctic Regions; D001419:Bacteria / Q000201:enzymology* / Q000235:genetics / Q000254:growth & development; D001673:Biodegradation, Environmental; D015169:Colony Count, Microbial / Q000379:methods; D042926:Cytochrome P-450 CYP4A / Q000032:analysis / Q000235:genetics*; D006838:Hydrocarbons / Q000378:metabolism*; D016133:Polymerase Chain Reaction / Q000379:methods / Q000592:standards*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012988:Soil Microbiology
chemical_list: D006838:Hydrocarbons; D042926:Cytochrome P-450 CYP4A