Metabolic Engineering to Create New Class of Nature-Inspired Corrosion Inhibitors

For decades, natural products have indispensable role on drug discovery. But, if natural products applications are limited to therapeutic uses? To explore new horizons, we have applied our expertise on metabolic engineering to heterologously overproduce a siderophore titled Yersiniabactin (Ybt) in E.coli . E. coli host offers advantages of rapid growth rate, easy and cheap large-scale cultivation and well developed genetic manipulation and characterization techniques. Siderophores naturally show great affinity toward metal ions and surfaces. We have tested directing this innate ability toward corrosion inhibition. Preliminary data demonstrates adding reduced quantity of Ybt leads to 50% decrease in corrosion rate of stainless steel in acidic solution, mainly due to preventive layer formation. Moreover, precursor-directed biosynthesis has been applied to generate new Ybt analogues with the potential for improved or altered metal surface binding capabilities. Novel analogues with higher binding constant and those with higher spatial surface area may enhanced corrosion inhibitory. Small molecules were characterized using HPLC and LC/MS. Corrosion study was performed using weight loss experiment and direct measurement by potentiostat . Our findings confirms nature can be a sustainable source for discovering new anti-corrosion small molecules which in contrast to common corrosion inhibitors are not environmental hazardous or human health risks.