Poly-?-glutamic acid (?-PGA) is a biopolymer with various industrial applications. Despite its diverse applications, ?-PGA of defined molecular structure is costly. Sustainable synthesis of designer-?-PGA was achieved with a B. subtilis 168 derivative as host. In-depth investigations of the metabolism provided new targets for enhanced ?-PGA synthesis. The developed strains and cultivation conditions demonstrate the huge potential of microbial ?-PGA for the use in industrial applications.
