Technical note : Rapid detection and quantification of microbes related to microbiologically influenced corrosion using quantitative polymerase chain reaction

Abstract Quantitative polymerase chain reaction (qPCR) assays were developed to detect and quantify bacteria and some critical sub-populations related to gas and oil pipeline corrosion. The 16S rRNA, dissimilatory sulfite reductase, nitrite reductase, and methyl-coenzyme M reductase genes were targeted for the quantification of total bacteria, sulfate-reducing bacteria (SRB), denitrifying bacteria, and methanogens, respectively. The results indicated our qPCR methods could accurately quantify all four target microorganisms with an accuracy of ±10% of their true value (95% confidence level). The assay sensitivities were 2.7 × 103, 20, 13, and 100 gene copies per reaction for bacteria, SRB, denitrifying bacteria, and methanogens, respectively. The comparison of qPCR assays and conventional growth tests showed that the conventional growth tests severely underestimated the target bacteria number in different growth media and did not accurately characterize the microbial community composition in the pipeline s...