Adaptation to hydrostatic pressure modulates proteome dynamics in corrosive sulfate-reducing bacteria

Microbially influenced corrosion (MIC) poses a significant threat to metal structures across various industrial sectors, leading to substantial economic losses and potential environmental damages. As deep sea exploration and infrastructure development expand, understanding MIC under high hydrostatic pressure becomes increasingly critical. Microorganisms in these extreme environments must undergo specific structural and metabolic adaptations to survive and thrive. In this study, we employed a proteomic approach to investigate the physiological states and corrosive potential of two sulfate-reducing bacteria (SRB) with different hydrostatic pressure optima. By simulating depths ranging from the sea surface to 3,000 m, we identified species-specific corrosion mechanisms and distinct proteomic profiles associated with pressure adaptation. These findings reveal opposing trends in corrosion rates, emphasizing the complex relationship between microbial physiology and environmental conditions. This study underscores the importance of characterizing microbial responses to hydrostatic pressure for improving corrosion risk assessments and predictive models, particularly for metallic structures deployed in extreme environments. IMPORTANCE Microbially influenced corrosion (MIC) is a widely studied phenomenon that continues to be poorly understood due to its inherent multifaceted nature. MIC involves complex interactions between microbial communities, their metabolic activities, and the surrounding environmental and material conditions. With the recent rapid expansion of human exploration into previously inaccessible areas, such as the deep sea, new questions about how the physiological adaptations of microbial communities influence their corrosive capabilities have been raised. This study investigates the relationship between corrosion in sulfate-reducing bacteria and the proteomic responses to environmental stresses in differently adapted organisms. It suggests that microorganisms sharing the same core metabolic pathways can drive corrosion through different mechanisms and highlights how hydrostatic pressure adaptations can impact MIC severity.