Science2Start competition: First place for CMFI PIs

Evi Stegmann and Wolfgang Wohlleben take first place with process for biotechnological production of the biodegradable metal chelator ethylenediamine disuccinate ([S,S]-EDDS)

The first place went to a team led by CMFI Principal Investigators Evi Stegmann and Wolfgang Wohlleben from the Interfaculty Institute of Microbiology and Infection Medicine (IMIT) at the University of Tübingen. Together with their doctoral student Naybel Hernández Pérez, they succeeded in biotechnologically producing a biodegradable metal chelator that is used as an additive in detergents, cosmetics and food, for example. The compound, which was previously synthesized from fossil raw materials, is hardly degradable in conventional wastewater treatment plants.

Evi Stegmann and Wolfgang Wohlleben's research has laid the foundation for the biotechnological production of ethylenediamine disuccinate ([S,S]-EDDS), an alternative to ethylenediamine tetraacetate (EDTA). The metal chelator EDTA is used commercially in large quantities in the textile and paper industries, as an additive in cosmetics and foods, and in medical products and agriculture, among others.

"The compound, synthesized from fossil raw materials, is hardly degradable in conventional wastewater treatment plants. EDTA is therefore increasingly becoming an environmental burden, and in some Western countries its use has already been restricted for certain applications. I am very happy to have worked out a solution to this problem with our research," says Evi Stegmann.

The metal chelator [S,S]-EDDS produced by the soil bacterium Amycolatopsis japonicum has comparable complex-forming properties, but unlike EDTA it is completely biodegradable. The biotechnological production of [S,S]-EDDS has so far failed because its synthesis in A. japonicum is already inhibited by very low concentrations of zinc, which is present as contamination, for example, in fermenters, glass vessels or media components. The first research work at IMIT dates back about ten years. Now, by means of "genetic engineering", the team has succeeded in generating an A. japonicum mutant that can produce large amounts of [S,S]-EDDS even in the presence of zinc. This mutant and the establishment of a simple purification process now form the basis for the establishment of industrial [S,S]-EDDS production.

The jury awarded the first three places in the Science2Start competition. The winners receive prize money totaling 4,500 euros and professional advice on spin-offs.

(Press release BioRegio STERN / Leon Kokkoliadis)