Sustainable production of fine chemicals by the solvent-tolerant Pseudomonas putida S12 using lignocellulosic feedstock.

The rising price of oil and impending deficit of fossil resources stimulate the development of alternative processes for the production of chemicals. The production of chemicals from lignocellulosic biomass is a promising alternative. Lignocellulosic biomass consists of a mixture of sugars that can be converted into valuable products or chemicals by means of bioconversion. It is essential that, in order to establish an economically sound process, the feedstock is utilized as close to completion as possible. However, due to its heterogeneous nature, lignocellulosic feedstock is often metabolized incompletely. This situation is also encountered during the production of aromatic compounds by engineered strains of the solvent-tolerant micro-organism Pseudomonas putida S12. This bacterial strain is not able to use all sugars from biomass, most notably the pentose fraction. Therefore, strategies were explored to engineer d-xylose metabolic pathways in P. putida S12, to enable the consumption of the most abundant pentose sugar present in lignocellulosic biomass, thereby lowering production costs of commodity chemicals.