Elucidation and Optimization of the EDDS Biosynthesis in
The complexing agent ethylenediamine-disuccinic acid (EDDS) is a structural isomer of ethylenediamine-tetra-acetate (EDTA). EDTA is widely used in paper, textile, and laundry industry, but also in cosmetics, food, and as medical additive. Due to its poor degradability, EDTA might become an environmental hazard. Its isomer [S,S]-EDDS has similar chelating properties as EDTA. However, in contrast to EDTA the isomer [S,S]-EDDS is easily biodegradable. Therefore, a chemical process to produce [S,S]-EDDS has already been established. Nevertheless we are interested in developing a biotechnological way to economically produce [S,S]-EDDS as an alternative for chemically synthesized [S,S]-EDDS. A biotechnological large scale production of [S,S]-EDDS was not possible until now, because already 2 μM zinc, a concentration occurring ubiquitously in standard media, inhibits the synthesis of [S,S]-EDDS. We developed a process to synthesize [S,S]-EDDS biotechnologically using an optimized Amycolatopsis japonicum strain, that produces [S,S]-EDDS in the presence of zinc and in rather cheap, complex media. The aim of this project is the elucidation of EDDS biosynthetic steps and the further yield optimization.
Project of Simone Edenhart