BIORENEW - White Biotechnology for added value products from renewable plant polymers: Design of tailor-made biocatalysts and new Industrial bioprocesses

Most industrial uses of cellulose require the previous removal of lignin, which is generally burnt at the mill. However, the chemical nature of lignin makes this polymer an interesting source of aromatic chemicals. Oxidoreductases are involved in both lignin biosynthesis and biodegradation. Therefore, they have the highest potential for modification of lignocellulosic materials and isolated lignins. However, the natural enzymes are far from operating optimally under industrial conditions. Some oxidoreductases have been extensively investigated in terms of structure-function relationships. This will allow a new approach based on tuning their catalytic and operational properties using protein engineering tools, such as forced evolution, and site-directed mutagenesis. The applications of tailor-made enzymes will include among others: i) increase of strength and other properties of cellulose fibres, and improve refining; ii) production of lignin-free cellulose for high-quality products; iii) production of lignin-based surfactants (as dispersants and nano-emulsifiers) and adhesives.