Enzyme-driven mechanisms in biocorrosion

Objectives (abstract of presentation): Recent works carried out in our team concerning enzymes and biocorrosion are presented at the meeting. For aerobic conditions, the direct catalysis of the reduction of oxygen on steel by enzymes or porphyrin was proved and a local electrochemical analysis technique (SVET) was developed to visualize the localization of the catalysis. On anaerobic conditions, the influence of phosphate species and other weak acids on the water reduction on steel was shown. The role of hydrogenase in biocorrosion process was also studied. Any conclusion: In aerobic conditions, many complementary contributions including enzymatic catalysis exist and can reproduce biocorrosion in the lab (MOB, GOD, hopefully porphyrin…) and even more inter-penetration of the thematic areas is still required. In anaerobic conditions, revisiting the previous lab studies taking into account possible involvement of phosphate species (common buffer) is certainly necessary and other mechanism than the FeS formation can also explain biocorrosion as the direct electron transfer between hydrogenase and steel material