Abstract
Quantitative real-time polymerase chain reaction (qPCR) is a highly sensitive method for the quantification of microorganisms in natural and engineered environments such as oil and gas facilities. This study developed in-field methods for sample processing and nucleic acid extraction from water samples, the design and validation of qPCR assays targeting Domains Bacteria and Archaea, and 3 physiological groups (iron-reducing bacteria, sulfate-reducing microorganisms (SRM), and methanogens) of corrosion-causing microorganisms. A novel, field-friendly method was successful for use in isolating DNA from water samples. Regardless of the water sources from the oil production field, the extracted DNA was sufficiently pure for direct use in qPCR assays. Additionally, all 5 qPCR assays were validated using a portable qPCR instrument. A novel probe-based assay was developed to target SRM. The computational and laboratory analyses showed that SRM primers and probes covered all known lineages of cultivated SRM, with favorable in vitro specificity. The findings illustrate the feasibility and value of the in-field method and portable qPCR instrument for molecular diagnosis of corrosion-causing microorganisms. The in-field method provides the oil and gas industry with accurate and actionable results in hours for decision making in corrosion treatment and remediation strategies.
