Effects of extracellular electron transfer on biomineralization by Shewanella putrefaciens in damaged organic coatings

This study reports the effect of extracellular electron transfer (EET) on biomineralization mediated by Shewanella putrefaciens in damaged coatings under different carbon source conditions. S. putrefaciens was able to obtain energy from metal surfaces to support metabolism via EET when the carbon source was insufficient. Under these conditions, bacteria colonized the coating scratches, resulting in accelerated corrosion instead of mineralization. The EIS results revealed that biomineralization was most significant in the 75% carbon source medium after 7 days of incubation. Interestingly, the pH of the medium increased with an abundance of carbon sources, which promoted biomineralization.