Pseudoalteromonas lipolytica accelerated corrosion of low alloy steel by the endogenous electron mediator Pyomelanin

Abstract Endogenous electron mediators are believed to be important bridges between microorganisms and electrodes, which influence the corrosion process. In this work, the genetically engineered P. lipolytica mutant strain with hmgA gene deletion, a hmgA restoration strain and a wild-type strain were used to investigate the impact of the pyomelanin on the corrosion of steel in marine broth. Weight loss and electrochemical data demonstrated that the corrosion rate of the steel increased when the hmgA deletion strain of P. lipolytica was inoculated in marine broth to produce pyomelanin, especially with the addition of L-tyrosine as a substrate.