Value of Next Generation Sequencing as Monitoring Tool For Microbial Corrosion - A Practical Case from Bioprophyling to Tailor made MMM Analysis

AbstractMicrobiologically Influenced Corrosion (MIC) can occur unexpectedly in any kind of system in which metal surfaces are involved, leading to integrity problems and economic loss. To manage and control MIC we need a clearer understanding of the microbial communities attached to the metal surfaces and how they influence the chemical processes involved in corrosion. There are several methods (e.g. biocide dosing, coating of materials, removing water) for controlling MIC, but the effectiveness of these methods depends on the type of microorganisms present and the prevailing conditions. A threat analysis is a multidisciplinary approach for determining the critical control points of MIC and with this, to manage the problems and set up mitigation strategies. One of the essential disciplines for understanding MIC is the understanding of the microbiology. Molecular Microbiological Methods (MMM) are increasingly recognized as important identification tools for MIC threat assessment. However, these current methods are based on known microbial systems and processes (i.e. sulfate reduction/sulfate reducing bacteria (SRB)) that are involved in MIC. However, if systems are less well studied, other MMM are necessary to perform a proper threat assessment. Here we show that Next Generation Sequencing combined with automated QPCR primer design leads to a methodology that can be used to predict MIC threats in relatively new systems. The identification tools are based on the total genetic (DNA/RNA) information of a sample and give insight in the present microbial communities and their potential activities. Thereby it becomes possible to assess MIC related threats beyond the current state of knowledge. In this paper, a practical case is presented in which the biofilm on metal surfaces in sea water was analyzed using NGS and further processed to determine the threat that MIC is responsible for the deterioration of the metal surfaces.